Damien Consensual unlock procedure, that's an intriguing idea. I'd be curious what the wearers (well the ones who have a say about it, I'll never get used to the concept of involuntary wearers) here think about it.
I think this is the only adult way to do this, otherwise you are someone else's prisoner, at least as far as wearing chastity gear is concerned. I could understand someone surrendering control over their body in some way as part of a game, e.g. some sort of BDSM-like scene, if they get off on that. But trusting someone else enough to give them irrevocable control, even for a period of time, no.