Hi, thanks for your question. For the most part, the city does have its own evacuation protocols, so while not all buildings will move beneath the surface, they should be making the proper moves to leave. Now if Raidou still wants to help, he will be welcome to, but he certainly will be prompted several times to prioritize his current mission.

There won't be any IC ramifications if he does not, however, if he does spent too much time evacuating people, he may have to wait at shore until the next wave of yachts arrive. Fortunately, there are still Kaiju to fight there, too.