CB Lam - 3D scanning and editing

Hello everyone! hope projects are going well for y'all, this is T rex skull I chose for 3D scanning, and I here are some problems I ran into during the process.

In this pic I am trying to fill up all the holes on the mesh. I had a hard time scanning the inside of the jaw.. and some of the holes are self-looped, so I need to expand the hole and refill'em..

Simplified, reduce polygons to 20000. the lower jaw still messed up. I decided to mirror the left side of the skull and finish the detail by hand, so I don't have to do so much on the computer

Gold T rex skull! hooray! Keyshot*

There's when I ran into troubles, I am still trying to figure out how to mirror and merge them..