Fortunately if you miss this, it's only an achievement so you can just start a new game, speed run to the Trevor introduction and get it done, and still continue on your main game save.
Something weird happened with my recent playthrough though.
-Drunk Driver (from restaurant near the marina)
-Hitch Lift 3 girl from Sandy Shores
Triggered shootout, Altruists Cleared
But on my Social Club checklist the Hitch Lift 3 did not show completed.
She kept showing up at Sandy Shores.
So I finally decided to just pick her up AGAIN (after she has already presumably died).
Got a prompt for the camp AGAIN (after they also have all already died).
And ... nothing. Gate closed. Climbed over, no one inside. (smoke coming from chimney's though)
Took her to where she wanted to go originally in Vinewood.
Hitch Lift 3 now complete..... wtf? Is this normal?
Can you take ALL Hitch Lift passengers to the Altruist Camp first, and then have to pick them all up again to take them to their intended destination to complete their events?
I already had the Altruist Acolyte achievement from a previous playthrough so I'm not sure if this is a bug.
It also annoys me that this miss-able doesn't show up on the social club checklist, yet it's a very involved shootout and there is somewhat of a prompt for it. Meanwhile, Simeon's miss-able random event doesn't prompt you AT ALL, but there is a nice BIG WHITE "NOT FOUND" DOT on your checklist map as well as a blacked out event square, to remind you that you missed something you didn't know about.