I can’t speak for anyone else. I know tone is hard to convey over text so this probably isn’t intentional. And I’ll answer your question. But I want you to know that this doesn’t come across as fun or playful or whatever. It comes across as dickish.
Yes. The Rhythm doesn’t have dedicated MIDI tracks, so you’d have to either turn the volume down on a sample or choose an empty slot. From there your keyboard will work polyphonically. But you can only sequence in mono. It’s also important to know that you can’t get around this by setting tracks to the same MIDI channel. Tracks can be on any channel from 1-15 but they have to be on their own channel.
I don’t own a Tracks so I can’t answer your other question.