:up: For them to meet in hell, both the speaker and the person alluded to would have to be dead. It's another way of saying 'It's the last thing I'd do', but with the added implication that the 'him' will go to hell (not a happy place, in Christian terms - it's where the bad people go when they die ;-)) rather than to heaven (where good people go).
A related expression (related by ideas rather than words) is 'You'll get X over my dead body' (that is, not at all - if I have anything to to do with it).
b