Add in some Tholian time travel to maybe even prevent the destruction of Romulus and you've got a world of possibles.
The thing is would CBS let Cryptic undo the idea that Romulus was blown to bits? I doubt it because it plays a big part of JJ Trek.
Actually, that's kinda it: they replaced Romulus with a proxy, and that got blown up, and everyone believed it was the real deal. Thus, JJ Trek happens, and the timeline happens.
But the actual explosion story happens here in the Prime Universe, in STO, so it can be followed up on. The explosion happened, everything happened, but we learn why/how and so on... no actual undoing involved, except for the perceptions of what happened.
Too late for Nero though Still be interesting though
Umm, unless there's actual time travel involved for our side, STO expanding on this theory simply means we'll understand more about how/why it happened, and getting a better look at the Iconian-Romulan 'relationship'.
So really, JJ Trek continues as normal, completely unaffected.