Yeah, I believe you'll send the $30. Then I send you Bitcoins. Then you issue a chargeback and get the $30 back.
There is now a service called EgoPay which may or may not be a service owned by Payza but this EgoPay service does allow an accountholder to add funds to an EgoPay account using Payza. EgoPay transactions then are non-reversible.
EgoPay just launched, as far as I know, but that might be a way to use Payza to buy Bitcoin (once a Bitcoin trader or two starts accepting EgoPay).