I don’t know what support had you do to reset the module or what files to manipulate, but here is what I would do now that you have verified it works w/the Tacx software.
- Throw Zwift in the garbage aka uninstall it.
- Remove the Bluetooth .plist file.
- Reset the Bluetooth module.
- Empty the trash.
- Reboot the Mac.
- Reinstall Zwift.
If you are not that familiar w/all of the above, here is a similar problem w/a link for some extra guidance: