I think to have success in the Thanksgiving Mission to get Maya's contract from her dad is of course due to your actions during the mission, but also after the mission when you're leaving, if you don't have a certain conversation before the mission, I think it was about doing the right thing or something, depends on whether you tell Derek to stop the car and go back.It is kind of strange. The failure state of the Thanksgiving mission is inextricably linked to DIK protagonists, who are very unlikely to be in the throuple relationship in the first place. For example, if you are a Chick MC you cannot punch Patrick, which is the single most significant share of suspicion other than talking shit at dinner. Also, when you are a DIK even the "right" dialogue options do not lower suspicion as much. However, a DIK protagonist can still tell Derek during the intrusion into the prep party that he is still into one of the girls. So it does seem like a way for a DIK protagonist to backdoor his way into a monogamous relationship with either Josy or Maya, but not both. That may be for the best, because even those in a relationship with both of them seem to be pushed toward the same sadistic choice.
I find it funny cause on every option I choose the neutral option when it comes to hitting Maya's dad or not, yet it doesn't always lead to the 'stop the car' option, on my first Jill run, I didn't get the contract, but I did a 2nd Jill run recently and I did get the contract. I've also got the contract on different type of runs, chick, neutral and DIK runs with all LIs with their associated affinity.