Mystery vibration at 25 mph can't be diagnosed. It's not the front end!

Re-read Bro, the shop refused to use the diagnosis tool the OP asked them to try. Nobody here said the washers were a fix, the OP understands this, the shop hasn't made
a diagnosis to solve it but refused to try something suggested to them. A prop-shaft swap w/a known good unit would be a good move if available,......relax a little.........

YOU re-read what I said. I said they were right when they told him it was not a fix and they were. I know eaxctly what I read. Do you?