This theory is supposing that the game as rumored could be related to multiple realities.

We know how Damashi/Onaga was tricking Shujinko while all the stories previous to MKD were happening.

Damashi was the essence of Onaga, that was able to manifest through multiple realms.

What if Raiden wasn't the only one able to send a message to his past self? Being able to manifest between different planes, it's possible that Damashi could learn about Armageddon's final outcome.

Even if he didn't, the results of MK9 could make Damashi change his plans an force them to go faster in order to get the One Kamidogu, as IIRC they were delayed in part because he still needed to recover his body, but maybe now with a more urgent situation he prefers to act faster to take advantage while he can.

Now, the One Kamidogu is said to be "the means of attaining ultimate mastery over reality".

It isn't in Onaga's interest to have Shinnokh forces riding all realms, specially Outworld, so what if in the meantime he has managed to form the One Kamidogu (somehow aquiring the sacred amulet from Quan Chi at some point) and is playing with reality? Maybe he wants to merge realities to make an scenario where Shao Kahn is effectively banished from existence like at the end of MK9 but combining it with how things happenes during the other reality? (which could explain human Sub-Zero for example) to take the best scenario for him?

Just a theory, but I think the kamidogus have a lot of potential here to mess with realities and all different planes of existance.

PS: In reality I hope the game isn't about multiple realities as that was supposedly last game. But I was thinking about that theory and realized the potential of those artifacts.