Is there a way to pull the liner back safely away from the wall in just that area and get it back on?

My plan (before filling the pool back to the top) is to order new gaskets for the return.
1) pull the return off,
2)clean the rust using a wire brush,
3)apply naval jelly/rust primer, to help slow/stop any more rust
4) clean that up. spray paint,
5) reinstall return.

6) open pool.