First, I really love your signature, lol. Second, I have heard of a lot of snakes refuse food once being moved into a even slightly larger enclosure. I know the previous enclosure may seem cramped, but as long as he had room to 1.) go potty somewhere not on himself 2.) get water 3.) have a secure hide, I think maybe moving him back into the old one would be okay. I am not suggesting it as a better or wiser decision because ball pythons often go off-feeding for months anyway, so he'll be fine for awhile I am sure even if he doesn't like this new enclosure outright. But I have heard of some snakes just wanting to be in smaller enclosures than what is often recommended. Is this the case for your snake? I don't know.
But it just comes down to preference, and hopefully others will comment and help, too on this one.