MIDI syncing to MIDI keyboard?

[Oancient1]

Another thread mentioned that the 2488 can do MIDI synching to an external drum machine. Can it also do MIDI syncing to a MIDI keyboard? How about the DP series, or the discontinued 788? What I would like to do is be able to use a MIDI file loaded into the Yamaha as backing synchronized to the recorded tracks, and have the ability to modify the levels, panning, and instumentation (not the bars and beats) the MIDI as needed to fine tune the backing. Anyone have any experience in this area?

Thanks,
Tom