How to undo file deletion on merge or rebase?

Question

git

Good evening, please help in solving the problem:
There is a release branch, emergency changes are merged into it. There is a refactoring / main wind, refactoring branches merge into it.
It is necessary to merge these branches, alas, they have already diverged a lot, and most importantly, most of the fixes in release and all changes in refactoring are connected with one huge component that is broken into parts.
When trying to do a rebase or merge, I got stuck with the fact that once a branch from refactoring was uploaded to release, and then canceled or simply deleted new files. Now when we move changes from the release branch to the main, the necessary files are removed from the main!!!
Tell me how to deal with this?