If your changing the wheel, just a tip, it may take a week for him to start using the new wheel as much.
Also Holly generally gets off her wheel to go the toilet, because she likes to keep her wheel and feet clean, when she was younger she just stayed on but once she reached 10 months old she started getting off the wheel to go to the toilet more, there is still SOME poo on the wheel, but not as much.
I genuinely got scared that she wasnt using her wheel, we then got a camera for her vivarium to watch her to see if she was or not, and thats when we discovered that she WAS using her wheel a LOT she was just getting off the wheel to do her wee and poo !!
Ali is so adorable !!
I think that its great that you want him to have that area for play, maybe you could use the old wheel when he's out in the play pen and then the new one in the cage, he'll get used to that, (also save taking out the wheel and putting it back after cleaning it every single night) but he'll then get to know pretty fast that he has a play pen wheel and a cage wheel.
I think keep something that smells like you in the cage will help too, to get him back to knowing your scent, if you just moved and he moved with you then he is probably still adjusting to the new house smells, even if his cage is all the same, but it could affect the bond in a small away especially as you took his beloved wheel from him.
You could always make up a new smaller tube maze, if he loved that a lot too.
I think, to re build trust, start off from the beginning, and work it back up, also as Aj.t said do more hands off bonding for a while too.