I'd have thought Aer Arann was a possibility for GCI-DUB (maybe even JER-DUB as well). Good to hear ZRH being a possibility again too, perhaps Darwin Airlines, which operates a seasonal service to JER?
I don't know what the story is with Jersey, but I'll try and find out. As for Twinjet, I wouldn't even bother - their schedule is useless. BE to CDG makes more sense, BUT the problem with BE is that it doesn't interline with anyone else. I wonder if that might be a factor? What we really need is an airline that does do that and if BE can't do it, maybe the Jersey authorities want to find someone who will - perhaps one of the AF regional partners.