My experience so far-

Up to 24 hours prior to departure, a 1K and 3P traveling together get upgraded together, seemingly at the same time as a 1K traveling on their own. A 2P on the same flight but different itin (but higher fare class) did not get upgraded until the gate.

Within the 24 hour departure window, the upgrades accrue individually, so that a 1K will get an upgrade that a 2P or 3P does not, even if they are both on the same itin.

Your situation stretches the limits a bit. I don't even know if, as a 1K travling with a non-elite on the same pnr, I drag that non-elite into an upgrade in the pre-24hr-window. It's possible that there is no advantage to the others whatsoever for being on your itin, and only potential disadvantage for you. I recommend ditching them, if at all possible. If you're worried about team spirit, then go sit back with them in E-. But there's not much good you can be for them, and if you can drag one of them up front with you, would that be a good thing? This is sounding like a Survivor challenge where the winner gets to bring just one other person with them, causing friction with the rest of the tribe.