See thewca/tnoodle#156 (comment) for renaming the variables, and thewca/tnoodle#156 (comment) for checking that pyraminx and 222 are always solvable in exactly God's number turns.
@chenshuang, do you think you can take this issue on when you've got some free time? There's no immediate rush here, but it's definitely something that should be done eventually.