Section 8 tenant won't give new address after moveout

[Alex Ballas]

I have a very difficult section 8 tenant who wont give me her mailing address to send her security deposit back (or whats left of it).  She demands I work through her case manager.  Both are very difficult people, so frankly I don't trust either of them.

Am i by law required to send her deposit letter to the tenant or can I legally be allowed to send to case manager if that is what is requested?