I had nearly the same problem & removed the trans. to check most of the same items, found no reason to not shift (but did not go inside). I went to 6+- "shops" near Daytona, most would'nt touch it....others did'nt seem to know mercedes (722.4), said it was electrical, or valve body(@ $2200.) including a "shop" on Mason ave.--found another shop, seemed ok, took it to him, he disassembled it, ALL friction discs were gone, a roller bearing was already falling apart, brake band scored,etc.( I saw the parts-IF, those were really out of my trans.?) he's still working on it, will post results when its done.....sorry to sound like you MAY have similar trouble..jerry.