TAC, Nat, and Cal cannot all be teammates, so you have to get off that idea. If you suss Cal, you probably shouldn't suss TAC or NAT and vice versa.
If I think both could be scum, but also that they are incompatible, and one flips town then I can feel even better about the other being scum.
As long as we are in the dark i don’t see why every suspect I have needs to be compatible as teammates with each other.