Heyo! The transmission is most likely fine. The guy working on it is fixing up lots of the engine installers mistakes like plug wiring routing, alternator position, cheap intake gasket, bad vaccum line routing, oil cooler line routing, etc. He's gunna get the AC going too, and put on this rosta cruise unit. He's just busy as hell. More cars than he can shake a stick at. He claims end of month, but I'm not holding my breath.
Hope you find someone to work on your van. Yeah, I've definitely experienced the folks who scoff at vans. They are lame folks who I don't want to give money to anyway. The guy I found here in Atlanta is really cool, super smart, just absolutely swamped and slow.