Thanks for putting it together. I believe you also need to push "-k" at the beginning unless I misunderstood how this part works. But I think this only affects running tests, i.e. after collecting, so it probably doesn't affect performance.
I have also seen that there are other options:

  --ignore=path         ignore path during collection (multi-allowed).
  --ignore-glob=path 
  --override-ini python_files (args):  glob-style file patterns for Python test module discovery

Maybe python_files is the one to use, but I also dont know if it will work since it may not support full file paths. 😞