Why my rear brakes/wheels make weird noises?

[Kenny Boxster]

Is it a possibility the accident may have been so severe it damaged the motor mount from the engine & transmission jolting forward? You should also take a look at the transmission mounts to see if any green/bluish fluid leaked out. As for the motor mount it's impossible to tell without taking the assembly out, so I could see if the mechanics could not see anything visually wrong. If you've exhausted all your options you may just try that. I don't like giving such a suggestion but the symptoms described can be mount, and a collision could easily damage such component.