There is a good chance he will lose it back.
You might try to get to the aff program via the casino customer service.
I have often found this to work when the aff program is unresponsive.
If and when (rare) I advertise programs that do carryover negatives, I always automatically stop all promotion the minute I am in the negative. No point in throwing money into a dark hole.
Likely your whale will climb out of there on his/her own accord.