The Trench Fighter uses the American Skin, so He'll be part of the American pack
I'll be updating the faction HMGs to use the Tripod if it doesn't fail it's field test, it'll just be a little time-consuming as I'm working on the American pack, Legolas, Gimli, and Boromir, and trying to beat Resident Evil 4 on pro mode for a snazzy unlock x_x
The Green Berets are split between the packs as they are a sub-faction, the packs are made after unit-types rather than squad-identity, hence why the Elite German troops were merged into the Officer and Infantry specs respectively.