I'm sorry this happened to you two.
I hope his feathers grow back soon.
In the meantime, like others have said, giving him other ways to increase his mobility will make this less frustrating. Also trying to pay attention to his signals on where he wants to go. Poppy was clipped before I got her in April, and has just gotten in a primary feather on each wing (still can't fly yet though). She uses headbobs to tell me if she wants to go somewhere, and if she's allowed to be there, I bring her to that place because she can't do it herself.