Actually, you can be forced to take Val and Alyssa, with no choice.Well, I have to guess that's why the option of not having Val come was included though.
Specifically, during the dinner event with the sponsor, if Val doesn't do at least two of the following three:
1. Hug sponsor when introduced,
2. Drink when prompted by sponsor,
3. Dance with sponsor,
then the MC is not given a choice by Jamal.
This is kind of perverse and seems to deliberately target those players who may have been playing a pure romance route, keeping Val away from everyone else. They are forced to see their LI(s) with other men, with no control over what happens.
Luckily, the Ren'py version of the game omits this logic, and the player always gets a choice, even if the choice isn't always a good one.
It doesn't help that with the MC passed out most of the time, we don't even get to see most of the sex scenes. But I guess that was done to limit the number of renders.