guess this might be one of the multitude of reasons why Discovery is a prequel, so that they don't have to deal with all those rights issues, and can wait until they are sorted out, either by the Kelvin-verse movies being discontinued as a whole (and ALL of their events being disaccounted), or Paramount and CBS merging Trek and them having access to all Trek events. (Might be like the Marvel/Fox Fantastic Four rights issues, where they simply have to wait untill some rights revert back, but need to paddle around the issues for their content in the meantime - by not having DIS be impacted by those events).
All of this is speculation though. At the moment I think the destruction of Romulus is entirely up in the air wether it actually took place in the prime universe or not. It was never intended to be further examined storywise, and it is mingled with the fate of the Kelvin-universe movies. So we probably won't see an answer to that untill the next generation of creators make a definite decision about that.