How to recover deleted files in git repo:
Find the last commit that affected the given path. As the file isn't in the HEAD commit, this commit must have deleted it.
git rev-list -n 1 HEAD -- <file_path>
Then checkout the version at the commit before.
git checkout <deleting_commit>^ -- <file_path>
Or in one command, if $file is the file in question.
git checkout $(git rev-list -n 1 HEAD -- "$file")^ -- "$file"