As far as I know, no, there isn’t any function that will automatically get what you’re looking for. You might be better off posting a new topic rather than adding to another question. It will be seen by more people if it’s in a new thread with no replies.
If you want to get all the fields assigned to a post type then you can get all the field groups with the function I posted above. Then you can loop through all the field groups and look at the location rules to see if they match the post type you’re looking for.
