Could be the guy that went missing near the women's camp, too - don't recall seeing proof that the walkers got him. Looked like too many women to be a group from The Kingdom.
Also, as Gabriel drove off before the opening credits, someone else was in the car with him. I would guess it was one of the women, based on the hair. Tough to tell for sure.
I totally forgot about Ethan, I think that was his name. He was with Tara when they got attacked by the sand walkers on the bridge. He would be someone that Rick would be amused to see. Ethan may have found and brought these people to help attack Negan. I remember Ethan having some issues and wanted to go on a 30 day run with Tara to gather his thoughts.
I agree that the group wasn’t from the Kingdom because of the next week’s clip shown during the Talking Dead. It showed the main fighter from the Kingdom still there. So they have to be completely Newbies, too many men to be the Amazons. Now we have Alexandrians, Kingdom people, a few Hilltoppers, Newbies and possibly the Amazons to join up to fight Negan. Maybe.
I FORGOT about that!! Tara found a key card with three P’s on it! Everyone assumed it was Negan’s group.... Your assumption is GREAT!