Indeed, it isn't clearly stated, but we can "play" with this idea with things both mods share. It's for fun, like kind of fun people have creating and exchanging theories about lore in games. Something simillar to Team ICO games, where each game is its own thing, but they share multiple similarities that enable players to connect three games without needing a big sign, or title that Shadow of Collosus is a Prequel to Ico.
Cunning gals might be as well directly connected to "Brutes" in X-Com Files where they both got an idea that eating Zombie Flesh is smart.
Weapons that appear just the same in both mods.
"Ghost" story arc and UAC existing in X-Com Files might directly correlate with The Dark Ones and the same organisation in Piratez.
It might be, or might not be, however there is more fun when there is no clear, big and direct proof that they aren't.