727 Problem

Since we can't see what was done, all guesses here. I would take it out and tear it back down. Always easier the second time. They are not as complex as most people think. Hopefully you are using the equivalent of a factory service manual. Take your time and follow the steps. Unless there was a part failure which you will see and need to tear it down anyway to fix, something is in wrong or out of adjustment. Lots of work but you will know for sure and not look back when it is done.
Just because someone is a "Dr." doesn't always mean he can do brain surgery or any other surgery for that matter. Everybody has a specialty. In my shop, normally brake mechanics didn't do tune ups...