Can I make an insight check on this “noble woman”

Go for it. You can just roll the check if you want without asking. Only if you want to re roll someone else’s check do you have to be proficient 

Sorry 

insight:4

"We're actually here on behalf of the Watch," Elero says, producing the Watch Writ.  He pulls it out, flaps it around, and then holds it up, smiling.

Mark finds it hard to see through the woman’s bluster. Although you can tell that the shifter isn’t very impressed with her manor. 

The Watch Writ frightens makes the noble woman’s eyes widen. “Oh my I’m sorry. Why didn’t you say so earlier? Cmon darling come on.” She whisks the shifter away who smiles at you all as they walk by.

When you enter the lift and look at the panels and find one panel of a Medusa, it’s easy to see that it can be pried open. Beneath it several wires connects the lift car to a small Eberron dragon­ shard. Each wire is connected to an individual pin-sized hole in the dragonshard.

"Ah, so this is what they meant by Medusa." Elero will connect the wires to get the lift working.  Let me know if that requires a roll.

Erix calls out to the Noblewoman

"Wait, is there any other way down if the lift doesn't work?"

No check needed, you've guessed the nature of the issue, and can work out that you need to reconnect a wire. The chamber comes to life and starts to move down. The lift seems to descend forever into the belly of Sharn. Several minutes pass as and the lift rattles and shakes, as if passing into some place it was not meant to go. This rumbling builds to a violent peak then the lift stops, and its doors open. By the lift's interior light, you can see into a vast, unlit cavern strewn with broken stonework from ancient buildings as far as you can see in every direction. The air is stale, and filled with dust and the scent of decay. These are the ruins of the cities atop which Sharn is built. Ahead of you yawns a fifty-foot-diameter, ten-foot-deep pit that seems to have been intentionally dug. You hear the soft sobs of a young child coming from a wooden shed on the far side to the pit. It is very dark between here and there though. You can't quite see what is in between.

Erix listens closely to see if he hears any animal sounds.

Perception: 13 

Not animal sounds per say. But you do sense their are people in the pit.

(Erix will in new environments always be on the lookout for new creatures he might try to befriend/tame)

"Hmm was listening for animals, but I think I hear people in the pit."

Kit giggles all the way down the rumbling descent before falling silent before the view of vast ruins. “…I don’t think this is going to be your good ol’ kobold gang fight.” He nervously scratches some of the patchier parts of his ginger fur. “Hear that? Gimme the creeps. And that pit?!.” 

kit wants to check if the pit looks dug with hhorrible monster or with shovels. 

investigation: 13

The pit was dug with shovels. Incredibly organised and hard working hands fashioned this pit.

Elero will pull a small clear crystal from one of his pockets, press it into the end of a block of wood, splitting the wood along the grain with the force of the push, and then take a few strips of copper from another pocket, fashioning a small cage around the crystal.  He'll hold it close, muttering the Magical Tinkering infusion, and the crystal will begin to glow, giving off bright light in a five-foot radius.

He'll hold it out to the party. "Here," he says. "I don't need this, but maybe it'll help one of you.  He'll hand it off to whoever wants it, and then cautiously approach the pit, looking around the cavern to see if he can see anyone or anything else.

Perception Check: 14

Mark will pull out rope and anchor it onto a sturdy piece of the lift, He will then toss the rope down, "Any of you can take this all the way down if you would like, I am not much for fighting up close so if someone else wants to take the light down there, it would be a great help." Mark looks at his new metal comrade. 

Just as you are all discussing who's getting the light and how to proceed. Five Goblins jump up from out of the pit. With your great perception checks they don't get the drop on you, but they are clearly here to fight. "Who the hell are these guys? Garra will want at least one of them alive." One of them yells to the others as they launch forward with their scimitars out.

I've rolled initiative for everyone again. Group 1 is up and can go in any order.

Group 1: Centurion, Elero, Evelyn, Kit

Group 2: Goblins

Group 3: Erix, Mark

Elero will drop the light at his feet. "Focus fire," he'll say, and fire his crossbow at Goblin 1.

To hit 10 and damage 9

He'll back up, if possible, trying to stay at range of the goblins but not lose sight of them.

That's one goblin down. "Hey, these guys think they're tough! They don't know who they're messing with." Four to go. 

Rest of Group 1 are up.

Kit shifts (BA) into his skittier, mangier self, and as he does he coughs up a fur ball soggy with eldritch energy. 

 Attck: Nat 20 for 26 total. Force damage 10.