I know you’d said that you have deleted backups, but the error code “the following scripts don’t match an existing file” indicates to me that it is looking in backups for the existing file to replace. I could be wrong, but again, no Mac to test and help out unfortunately.
The one thing which may be obvious but I do have to ask is whether the mod was successfully activated from the mod panel after replacing all of the files manually. The only time I can recall seeing anything like that was when I’d just forgotten to activate the mod and started the game with the replaced files but no mod active.
The other option may be to just go into “files/scripts/“ and copy the “Aricsexpansion” folder into your base game as well. That may resolve the issue of it not being able to find and replace the files.