Via mime it is demonstrated that these three communities (forest, hanging rock, lake) that they used to trade with are gone.

Well, that's... bad... what about any farther-off communities?

"New London", "Winterhome", "Frostcrown", "Broken Inlet", "New Sheffield". Each with a vague gesture towards a blank part of the map. There's probably some out there, but it's too dangerous to go exploring far, especially with their gear breaking down over time.

One of the five with the symbols comes over at the mention of "New London". They're from there, apparently! He starts talking up about how great the place is (it's mostly not very comprehensible, unfortunately). The holy symbol gets held up and referenced a lot. The rest of the survivors seem annoyed and resigned to it.

...will they by any chance hand him a broken object?

....Sure? Here's a bow with a crack down the wood.

"Mending."

WHAT. HOW.

The New London crowd think this calls for a group prayer. Someone else points him at a burnt out lightbulb on the wall.

He doesn't even know what that is but he can cast Mending on it!

It starts emitting light.

Wow. Uh. 

Here's more broken things? Rusty tools, torn clothes, lanterns with broken glass...

He can't actually do much about rust, but if they got rusty because they were broken in some other way and then not maintained he can fix the original problem so people can de-rust them the long way. The others are all yes-es unless there's missing parts.

What about- He is shuffled to a workshop- This very fiddly bladed fan sort of jig with a hairline crack right down the middle? The way they treat it, it seems like critical infrastructure of some sort.

Longbow Lady, among others, watch with intense anticipation.

Mending!

Joy and celebration!

A team of four takes the thing down to another room full of large metal things and starts carefully installing it in a large metal thing.

It takes a few minutes, but they carefully nurse the controls along until the metal thing is rumbling steadily. It sounds a lot healthier than the groaning clanking of the other one- Which is promptly shut down after some consultation of steam gauges. It leaks sticky black oil over the floor as it shudders to a stop.

Huzzah! They're not all going to freeze to death! Oop, they're breaking out the booze.

Not his thing. Anything else he should spend ten minutes chanting over?

They weren't quite prepared for a sudden repair miracle. They don't have critical broken infrastructure already lined up. There's a couple more big objects- Motors and pumps, mostly- But people proffer heat lamps, torn packs, weapons, that sort of thing.

Sun's going down, eventually.

He should maybe figure out where he should sleep before it's dark, though the mended light globe is helpful.

There are lightbulbs here and there; Most are broken.

He can have his pick of rooms in the warm part of the hulk, once they understand what he's going for. Some of them may even have been properly originally designed as bedrooms, with metal bed frames built into the wall. Small and private, large and shared with plenty of blankets, or Longbow Lady's room offered with a wink.

Oh dear. He'll take small and private.

The room is warm. A buzzing steel radiator sees to that. He's undisturbed overnight.

The radiator is neat!

He dispenses with the armor and the padding, adds his coat to the pile of blankets just in case the radiator is going to need mending in the middle of the night, and sleeps there.

They apparently have a wakeup horn. Just before dawn, it BLAAAAARs out, boneshakingly loud, for about five seconds.

The only reason you would have something that would wake up your wizards like that would be if it were a DIRE EMERGENCY. He leaps up and gets the armor on as fast as possible and charges out with his mace drawn.

...They don't seem to be having an emergency? People are queueing up for the bathroom in the hallways and rubbing sleep out of their eyes perfectly calmly and are kind of alarmed at how he's alarmed, now.