We have had the same issue. Luckily so far only 1 person has booked through their personal TA. We put on our wedding site our TA info, also in our invites obviously and I try to send out updates constantlty on the status of our rooms. So I will email out through our site saying "We are getting closer and we are down to 3 available rooms! Book now for only $150 down and have the leisure to make payments through our TA" So basically I am selling my TA and not the resort itself. Then again we only are booking around 20 rooms.
So sorry, try not to stress, everything will work out in the end =0)