The option `--preferred-package` does not change the loading behavior of `spoof.py`

I have two resources with the same name:

./bin/resources.py --types=config | grep verafinger
  + verafinger           --> bob.bio.vein.configurations.verafinger
  + verafinger           --> bob.pad.vein.configurations.verafinger

When executing spoof.py, I want to use the second one, not the first.

For some reason, if I pass the --preferred-package=bob.pad.vein option to spoof.py, then it still doesn't respect the preference and continues to load the first configuration resource instead of the second.