I think I understand what you're wanting to do and Simon has it right. The keyboard will have a specific channel output for midi or it will broadcast omni. One or the other. You set it to the correct one.
In omni mode it should put all the midi into that one track without any issues. Splitting it back out to individual tracks, I'm not so sure how you would do that once it's into a track as omni.

Like I said, it's bee a very long time since I worked with midi and I was certainly no expert even then. But I do believe you would need to work in a DAW that lets you record multiple midi channels simultaneously. This stuff hurts my brain now days..... hence the reason I work in the audio realm mostly.

You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.