Welp, I just came up with some late-night speculation about the plot... hopefully this is the right topic.
Don't open the spoiler until you've read my attempt to connect the dots.
Mental Omega takes place in the early 1980s, and yet even before the beginning of the Third Great World War, military technology is in many ways far ahead of our own timeline in the 21st century. With robotics, energy weapons, teleportation, weather manipulation, atomic weaponry, genetic enhancement, psychic manipulation, subterranean transit, aeronautics, anti-gravity, invisibility, and other marvels of science somehow leapfrogging within a mere generation, one has to wonder how this is all possible.
Setting aside the fact that a few physics-denying absurdities are a legacy from the Red Alert 1 conflict, things seem to be moving very quickly (to the point that the Epsilon Army, and later the Foehn Revolt, could develop their entire arsenals in secret, apparently in an incredibly short time-span). Obviously several scientific geniuses had some roles to play in this (Yunru, Rashidi, Siegfried, all the folks at Kanegawa and Steinstech...), but it still seems implausible that such amazing progress could be made in such a short time.
Speeder at one point said that "the advance is mostly due to war against Stalin.. and for certain other reasons."
That made me curious, since it sounded like he was deliberately foreshadowing something. He also said, a little more specifically, that "Timeline/universe tie-in[with the Tiberium Universe] will be hinted at in Act Two."
Of course, it's common knowledge that in GDI mission 08 ("Paradox Device") of Twisted Insurrection, the Nod Da'at cell (which "specialized in psychological warfare"...) was revealed to be somehow in possession of an alarming relic: a GWWII Chronosphere. In fact, they managed to perform at least one (presumably successful) chronoshift with the device — and considering Einstein's original use of chrono technology, to travel backwards in time, it is theoretically possible that they did exactly that.
This has all been pointed out before though, including how those mysterious events might relate to Mental Omega's timeline: perhaps a Nod agent... possibly Yuri himself... traveled back to the era of Stalin.
Except, how would that explain the advances in technology? Whoever traveled in time would have to be an extraordinarily gifted and knowledgeable scientist, able to recreate mid-21st century Nod technology in a few years or decades — and much more. On the other hand, perhaps we could remind ourselves how Nod's technology managed to skyrocket in the first place. No, it wasn't just the genius of the otherworldly prophet Kane.
Perhaps that unknown time-traveler brought something with them — something like the Tacitus.
Sometimes the answers could be right in front of us all along....