Could you please add
.pak
.ucas
.utoc
as blacklisted file-types as these do not compress well.
Other examples would be Granblue Fantasy Relink (.0-9) where one file went from 61.2 GB to 4.83 GB which is impossible.
As for Unreal Engine 4/5 files. While this does not effect all UE4/5 games, it does where the game gets compressed by more than 1% meaning they get squashed by like 80% which makes the files unreadable by the executable and also overwrites the file essentially making it contain dummy data.