Bonehead move on my part - was there any way out of it??

[bav]

I think because of action behind, whether the original all-in guy moved chips or not OP is SOL. His all-in behind the first all-in may well have influenced the next two hands to fold while had OP folded they woulda called. He can't all-in, screw the pot up for the original all-inner, and then say "sorry, didn't mean it, give it back".

IFF OP figured out before anybody else had acted that he'd goofed, he MIGHT be able to get out of it. (I wouldn't hold my breath.) But no floor should let him out after two people downstream folded to his all-in.