I completely understand your concern. When I was having trouble with mine, any abnormality in behavior totally freaked me out. It obviously would have have been better for the nem if it could have remained in the tank and you could have removed the crab but given your situation( not being able to catch the crab) i think you made the right choice. At least that is what I would have done. I dont think you killed it though, im sure the already unhealthy nem, coupled with the stress from thd move, could be the culprit for the extended deflation time. The nem is prob short on energy from being "sick", then add in the move, and the amount of energy it takes for them to deflate ( do a water change) and it was prob maxed out. It will likely re inflate in time just needs to recover some energy first. As long as the tank you moved it to is established with good parameters and sufficient lighting i think it stands a pretty good chance. That is, so long as it was the crab distressing it, or the stressor was isolated to the other tank. Keep us updated please, i hope it makes a full recovery!!