Delmalis moves back to the entrance of the tomb to keep an eye out for anyone on the way.

Perception: 15

"Some of these relics look magical, if you want to set them down and give me a few minutes, I can Identify them for you." 

Meep starts ritually casting Identify on the harp, and if there's enough time, the robe too. 

Meep, you ritually cast Identify on the items and here's what you find. 

The harp is actually an Instrument of the Bards, specifically the Anstruth Harp. 

An instrument of the bards is an exquisite example of its kind, superior to an ordinary instrument in every way. Seven types of these instruments exist, each named after a legendary bard college. A creature that attempts to play the instrument without being attuned to it must succeed on a DC 15 Wisdom saving throw or take 2d4 psychic damage.

You can use an action to play the instrument and cast one of its spells: Fly, Invisibility, Levitate, Protection from Evil and Good, Control Weather, Cure Wounds (5th level), Wall of Thorns. Once the instrument has been used to cast a spell, it can’t be used to cast that spell again until the next dawn. The spells use your spellcasting ability and spell save DC.

You can play the instrument while casting a spell that causes any of its targets to be charmed on a failed saving throw, thereby imposing disadvantage on the save. This effect applies only if the spell has a somatic or a material component.

Notes: bard, Healing, Damage, Control, Buff, Utility, Combat, Instrument

The "robe" is actually three items called "Lord's Ensemble." 

The Masked Lords of Waterdeep don this ensemble when meeting with one another. This raiment renders each lord indistinguishable from the others. The ensemble consists of three pieces — a helm, an amulet, and a robe — that function as a single magic item when worn together, but only within the city of Waterdeep and its sewers. You become attuned to the ensemble as a single item.

Lord’s Helm. This bucket helm covers your head and conceals your face. Screens over the eyes help to shroud your identity without blinding you. While you wear the helm, your voice is magically altered to sound genderless, and you are immune to magic that allows other creatures to read your thoughts, to determine whether you are lying, to know your alignment, or to know your creature type. Creatures can communicate telepathically with you only if you allow it.

Lord’s Amulet. This amulet bears the crest of Waterdeep. It functions as an amulet of proof against detection and location.

Lord’s Robe. This elegant robe functions as a ring of free action, and it creates the illusion that you have a nondescript, androgynous humanoid build and stand 6 feet tall.

Demalis, you don't see anyone coming but you do hear footsteps, as if it's inside of the room. 

Delmalis, being slightly paranoid, pulls out a packet of dust he's been hanging on to and throws it up in the air as close to where he can hear the footsteps as possible.

Dust of Sneezing and Choking

 Demalis, you throw the dust where you hear the footsteps and for a moment you don't hear anything. After a few seconds, you hear a "Well that's rude."

You watch as a ghost materializes in front of you. He's a human  with pale-blond hair and wearing a expensive, but gaudy, green clothes. He moves his hands as if waving away the dust. "I'm grateful you took care of that spoiled prince but you don't have to make a mess." 

Mable realizes the newcomer in the room and points at him. "Danilo Thann?"

The ghost smiles. "At your service. I sense brave heroes among you." His demeanor changes as he notices Roland and raises a fist. "Roland ...You dare come into my resting place. After what you did."

Roland also stops what he's doing and smirks. "Hello Danilo. I still see you're as pompous as ever in death. The eye looks good by the way."

Delmalis shrugs apologetically, "I beg your pardon, sir, but we've been dealing with devils and I was concerned that your footsteps belonged to an invisible intruder."

"It's fine," Danilo says to Demalis. "I would have done the same thing. Yes that so-called Prince was looking through my tomb, hoping to find his father's 'dragon.' I'm assuming the dragonward is still up. He said something about a Master Harper knowing where it was, but I'm not that. I mean I was a Harper at one time, but I never achieved so high a rank. Not like my father-in-law or my uncle Khelben." 

Twitch bristled at the ghost but contented themselves with just staring intently.

Meep holds up the book. "Was this yours? May I study it?" Then, a thought strikes him, and he says to the group, "If there's more than one 'master Harper,' we may want to check the other crypts to see if they're being raided as well!"

Danilo turns to Meep. "That's my old spellbook. You'd probably get a lot more use from this than I would. I don't think you'll find any other Master Harpers buried here, not in Waterdeep. Perhaps there's one in the city he wanted to find like Mirt the Moneylender."

Inside of Danilo's spellbook you find the following spells. 

Meep's eyes gleam as he flips through the spellbook. Without lifting his head from the pages, he asks "Sybil, aren't you friends with Mirt?"

"I wouldn't say friends per say. Good work comrades I guess. We help each other do things here and there," Sybil mentioned with a shrug as she rolled up the map and put it away for now. 

Delmalis looks slightly confused, "So are we staying here, racing to one or both of these people to warn them or help fight off Sunblight's agents, dragging the body to the guard, some combination of these or something else entirely?"

Twitch shrugged, they still weren't quite sure what the hell was going on but were happy to help however was needed.

Roland nods. "We could probably go see Mirt and check on him, or go back to the manor." 

Delmalis shrugs, "I guess let's go see Mirt, but we should probably bring the body. Don't want someone coming along behind us and bringing him back, right?"

"Unless we have something else, i guess we should pay him a visit unless one of you can send a message," Sybil questions as she readjusts her cloak, "I dislike dealing with people,"

So is everyone in favor of going to Mirt's manor, unless someone can send a Message as Sybil suggested. 

"I can help with the corpse part," Meep says, as he casts Necrotic Feast and touches the body of Sunblight. "This will make sure he can't be re-animated. And he'll be easier to carry." 

(You touch the corpse of a Small or larger creature that was slain in the past hour. You gain 5 temporary hit points, which last until the end of your next rest. The corpse shrivels up and can't be animated.)

Meep you cast your spell and there's a little bit of catharsis when you do it. Roland volunteers to carry Sunblight's body. 

As you all begin to leave, Danilo waves goodbye. "Thank you again. You have made allies of House Thann. You are all more than welcome to visit my tomb. Except for you, Roland."  

When you arrive to the surface, you notice screaming and the shouts of "Dragon!" There's panic and the Watch is trying to keep everyone calm. Meep, you see Johnathan the Magimuscular and his half-orc friend Quarlton trying to usher everyone to safety - JMM was the one who took your paperwork at the order and Quarlton had the zucchini stand at the Festival. 

JMM sees you Meep and waves you over. "Thank the gods. There was a dragon sighting over Waterdeep and everyone is in a panic, but we don't know where it's located.

As this happens, you see a large dragon come into view. It's exactly the same as the figurine you saw - the one Roland tried to grab before Mable smacked it out of his hand.