Something about PrimeSpock, despite taking a vow of silence about future events from his universe, anonymously letting Starfleet know the location of the Botany Bay in the hope that they would avoid it or take Khan's people into custody while they were still popsicles. Instead, Admiral Marcus took advantage of this information to find Khan and use him to his own ends. NuSpock does some research and concludes that only PrimeSpock could have known Khan's location, which is why he contacts him for more information (okay, that will probably be a couple lines
That would resolve a few issues as well, though like Ovation
, none of it is a big deal to me.