Airportable post=209086 userid=5200I’m flying by the seat of my pants (Jockettes)on this one. But if you bung up the holes, bar one & apply an industrial vacuum to that, you might reduce its volume by that tad you need for it to pop out.
M

 Nah I think you'd need a bit more of a vaccum than you'd  be able to generate with a domestic or even comercial vaccum cleaner,  if I were to go that way, I  suspect I'd be more likely to get results by enlisting physics to help if I could fill it with hot water, seal it, and somehow shock cool it.......it will collapse, but how to do that without crushing it to the shithouse is the question ? Too risky really. And the problem outer dimensions probably wouldn't contract, it would just suck the sides in.
The problem is really one of chemical reaction, I suspect a subtle blend of time, psychology and extreme violence will win out!