Well once you find the conclusion, you can then identify which premises (if any) help support the conclusion. As without a strong foundational support, a conclusion can be very weak.

But that assumption is made irrelevant because of the statement "Walt is a member of the Disney Vacation Club.". Whether Disney Vacation Members are the only group allowed to access a Genie pass is made irrelevant, because of this support claim.

The point isn't about whether an argument is grounded in fact (Remember the Disney argument). Its more just, "how strong is said argument's reasoning"?

Here with the tiger argument, its two assumptions. A tiger is a mammal, and aggression combined with the tendency to attack people is something undesirable for a pet.

For the LSAT at least, our goal isn't determining whether an assumption/s is incorrect/correct, but whether it/they are weak to any form of criticism, or have any flaws.