Its unfortunate, but you are in a position of having to believe one of the following things:
1. A person in accounting, who tells you that there will be no PTO submittal until payment, which matches what everyone else was told / previous tesla policy on PTO, etc.
2. Some random support person who tells you something that directly contradicts the above, and says that they will submit PTO without final payment.
If i were in your position and thinking about believing person 2 (which, I do not, btw), I would want something in writing, from person 2 stating that my PTO is in process and final payment is not required to process PTO. I doubt you will receive such assurance in writing, however.