Is there a way to determine how many more ranked rounds I need?
No chance to see it, as you haven't played a ranked round (RR) since October, apparently returning from a hiatus(?). No offence intended - just stating the visible facts.
Perhaps, this may work:
Play one desaster round (e.g., only bogeys) on a genuine course (9 holes suffice) and come back with the score and your raised average. From these numbers, an educated guess on the no. of rounds counting will be possible.
It won't hurt you, as it will be erased immediately when your average saturates eventually.
Next, play RRs to advance. I'm guessing that you might need 200(???).
Unrelated: Stop buying CC passes - your CC doesn't need them IMHO.