there isn’t unfortunately. (no to both.)
(might want to try going through the generic remote-assignable commands though; it’s detective work but you may find some nice surprises there. lots more on top of what’s available as a regular keycommand. just not this very feature i’m afraid. what you can in fact find as assignable commands via generic remote is to ‘open insert # X’. you could then send 8 midi commands via GR to open up all 8 potential inserted GUIs on a given channel. again, not the best way of interpretting the concept of ‘user experience’ by steinberg.)