The only gamefowl I have is an OEGB.I am aware that junglefowl were first domesticated to be fighting cocks. That doesn't change anything. If you tried to completely recreate gamefowl with a couple of junglefowl, a possible gamefowl mix, and an Easter egger, it would take an extremely long time, and they wouldn't turn out the same. It's better to create some sort of project breed with a lot of game in them, or to get purebred gamefowl and carefully breed in the traits you want while also keeping them as game as possible in other aspects.
I'll share with you of the results of the project if you'd like?
I understand it'll take a long time to complete, but it's just the fun of it that counts.