I second the EMDR. Either that or TF-CBT. They are the flagship therapies for trauma and have real evidence they work.

It was a different nuclear disaster in America. Not as bad as Chernobyl

What about trying a pressure vest? Like a thunder jacket, dog anxiety vest, thunder shirt, that kind of thing. The pressure is supposed to calm dogs nerves. You could also talk to the vet who could prescribe medication for her.