I don't think there is a way to do that. Most incoming MIDI information is designed to be sent to the sound engine, to a sequence track, or back out through MIDI. Akai never implemented sysex commands for the sequencer, that probably would have been a way to do this externally.
You could get creative and mute a program or part externally though. For example you could have a program set up for MIDI channel 3 that does bass only. You could then send a MIDI CC 7 (volume) value of 0 to turn the volume off (127 back on). Not so easy, but doable.