Vanizi again targets the zombie (pink) near Davis with her Eldritch Blast. 
(Ranged Spell Attack: 16, Damage: 10)

Then, taking note of Davis' injuries, she motions towards him, causing a healing light to wash over him. (Healing Light feature - Bonus Action - using 2d6: 7 hp)

Round 5:
Katarina chops down one and moves to destroy another (red) zombie, swinging hard and often at the previously uninjured creature.
Vanizi fires her eldritch blast at the pink zombie, then causes a wave of healing light to wash over Davis! (DC15 Fort save for pink: 9)
Davis knows a successful strategy when he's doing it, and so continues acting as armored bait.
Halyqwyn 
Zombies:
Red  
Pink 

Seeing that all but one of the zombies have been vanquished, Haly moves her focus to send the radiant light over Red.  DEX save 14 or 3 radiant damage.

Red dex save: 15

The red zombie has a more fluffy target than the metal man, so it turns and swipes at Katarina! (Attack: 16 Damage: 2)

Round 6! Party is up =)

The zombie's attack just BARELY misses the tabaxi, its rotten fingers sliding across her shield... she smiles as she retaliates with her longsword...

Longsword vs. Red:
Attack: 17; Damage: 8 (6 + 2 RAGE bonus damage) magical slashing

With one zombie left, Davis raises his hammer and swings.

Attack Warhammer: 20 bludgeoning damage: 13

DC18 Fort save! 6

The last zombie falls lifeless once again, and silence finally descends once again. What was once a serene crypt now lies in ruin. Two chipped stone pillars brace the vaulted ceiling. Tombs are cracked open, and corpses lie still on the ground. At the center of the room’s west wall is a dirtied and desecrated shrine bearing the image of a blank scroll. DC 10 Religion check:

With the threat taken care of, Halyqwyn looks around the desecrated crypt with a feeling of sorrow.  She heads over to the shrine and tries to make sense of what it once was.

Religion: 17

"This image of the blank scroll, it's the holy symbol of Oghma, god of knowledge and patron to bards and wizards."  

Halyqwyn also discerns that if they clear off the refuse and debris and offer a stirring performance or magical power to Oghma, this shrine could be rededicated. (DC14 Performance check or cast a spell of 1st level or higher into the shrine)

There is another passage leading east, south of the tunnel you came in from...at the edge of your vision you see the passage opens to the south and continues to the east. (Map)

At first, Davis doesn’t recognize the symbol, but after Halyqwyn mentions Oghma, he nods. He walks up to the shrine, closes his eye and channels his divine energy and casts Protection from Evil and Good into the shrine.

He then turns to Halyqwyn and asks “Do you have any healing you can spare? I can heal myself a bit, but not fully, and would like to keep a little healing left for any critical moments.”

The shrine is still covered in filth - the spell alone doesn't appease the gods...

Vanizi nods as Halyqwyn mentions Oghma then watches Davis cast a spell. "Hmm, I'm not sure that did anything," she comments.  When Davis asks the half-elf about healing the half-orc steps over.  "I could provide some healing. I've got one more spell to cast, but that would be it until I get a chance to rest."  She thinks a moment. "I could spare more healing light too, if you like." 

(So what's next? There is nothing else of value in this chamber, and one other exit leading east...)

Katarina looks herself over... surprisingly, she's completely unharmed in spite of her reckless way of fighting.

"Katarina is happy to keep going whenever everyone else is," she says as she wipes her blade clean.

With no response about healing, Vanizi takes a look about the chamber. "Ohgma you said? He has something to do with scrolls? I guess we could at least tidy this place up a bit. Put the shrine aright." She sets about quickly removing any debris and straightening up the shrine. "Anyone else have ideas?"

“I’ll gladly accept your healing magic” Davis says to Vanizi. “Or we could take a short rest here, catch our breath if that is helpful for others?”

Hoping to finish what he started with his spell, Davis will recite a poem he once heard about Oghma.

Performance: 13

If nothing happens, he will ask the others if anyone has anything they can offer to help rededicate the shrine and bring some good back to this crypt.

Vanizi works on her clean-up efforts as she hears Davis recite the poem about Oghma. "Very nice. I can certainly heal, but we should decide if we're resting or not. That would allow me to recover some of my magical energy, so it might determine how I heal you.  Personally, I'd be fine to wait a little before we rest." 

(OOC - I have 1 of 2 spell slots, so if we short rest, I can use the slot to heal and then will get them both back after the short rest. I could probably stick it out a bit and rest later after another encounter probably.) 

(Sorry - been a busy weekend)

"Of course, and feel free to ask any time, I don't always pay attention to that."  She rubs her hands together and lays them on Davis's shoulder.  A blue light glows from underneath her palms.  (Sorry, rolled terrible - 5 hp to you)

Halyqwyn turns to Vanizi and sees what she has done with the shrine.  "Oh, that looks much better."  Turning to Katarina, "You sure you're alright?  You and Davis were both in there head first!  But yes, I'm ready to see what else this area holds."

The shrine once again looks (and more importantly, feels) right and favored by Oghma. It glows with white light, and both Halyqwyn and Davis would sense that this light can keep undead creatures, like the zombies, away.

There is nothing else of interest or value in this room - just another exit south of the one in which you entered and leading east. It goes straight for about 35'  before opening to the south in a triangular shaped room. A double door made of green-tinged stone seals off further progression into the catacombs to the south. Facing the double door is a large carving of a grinning skull; one eye socket bears a wide eyeball with a jeweled iris, while the other is an empty divot.

The passage continues to the east another 15' before taking a sharp right turn to the south. A foul stench vaguely emanates from this direction...(map)

Vanizi walks away feeling satisfied they've made the shrine right. As they enter the triangular room, she says. "I'd guess to the south? Think these doors are locked?"  She wrinkles her nose at the foul stench coming from the direction of the continuing passage. "I do not want to go that way." 

Given another moment to look at the double doors, she does wonder about the skull carving. "I imagine there's nothing to that carving right? It's just a decoration?"