I am sorry that things have been rough!
They're both spayed, so that's already covered. The only things I can think of right now is maybe try the tub again but use distractions. Do they have favorite treats like banana? Sometimes food causes aggression but I found that it had the opposite effect on my bunnies, I made sure each had a good pile in front of them.
Also, have you tried stress bonding them? Are they scared of the sound of the vacuum or music? You can also try putting them in a carrier and driving around in the car.
Hang in there! I hope something gets worked out soon. I'm sure others here on BB will have some good advice for you.