One thing's clear: Everyone doing their own thing while trying to get at the dragon is not working.
Everyone TPing in there and surrounding it might get a few people killed, but it's the best chance to get the dracolich down. Otherwise, it's going to eventually recharge its breath, and if everyone doesn't all run in different directions, eveyrone's gonna die. (Running will only delay the inevitable).
Also, the Skraggs are a waste of time and resources, really, and TPing will get you away from them, at least temporarily.
Speaking as a DM who's "on your side" (in spite of throwing nasty threats at you and not holding back much), I think it's one of the only options at this point.
I honestly don't know how this is gonna go, but hasn't looked good up til now. I guess another option would be to flee... but I'm not sure that THAT would get very far either.