That's one way to look at it.That's the thing, we've already seen Master Chief, a lot. He's the star of almost all the games and a fair bit of the books iirc. More interested in exploring the other characters and developing our own than just trying to follow John/Blue team around or trying to rehash canon. We will see him, he's not going to stop doing his thing just because we're here, and even if they all survive/don't wash out, there's still only 75 of us, we'll all kind of know each other.
Another is that half the Fun for Quests like this, at least for me, is having the Player Characters interact with the Heroes of the Franchise the Quest is based out of.
Also: There is a BIG difference between interacting with or even being Friends with Jon and "rehasing Canon". That one's not gonna happen anyway because of the very Nature of a Quest that relies on Dice-Rolls.