How would Celebrity Greed work? All I know is that, even if a contestant gets a Q wrong, they still get a designated amount for their charities.
I assume you mean "if a contestant loses a Terminator round" instead of "getting a question wrong," as if the team gets a question wrong, they end up with nothing (except for any Terminator challenge money the individual players earned).
The "obvious" answer is, there is some minimum amount each celebrity is guaranteed, like on WWTBAM.
I would put in a couple of gameplay changes; no Terminator rounds, and, after each question, each celebrity has the option to stop, the way the game actually worked with the final question.