Transfer App Fee Waiver?

For transfers, I know that the Common App fee waiver applies differently according to the schools you apply to.
I’m pretty sure USC accepts the Common App fee waiver, but what supporting document/letter should I get from my financial advisors at my current school so that they can approve the waiver?
And which address do I send that documentation? Through email/mail?

If anyone has experience with the Transfer Fee Waiver for USC through Common App…please help!