Sysex control of MB's modulation matrix

I see MIDI parameters for assignment values, but I don’t know how to toggle on/off the matrix assignments. For example, I can adjust MIDI CC #23 which would be the Steiner Filter cutoff. But how do I use MIDI to make the assignment in the mod matrix for LFO2 to adjust that parameter? (The equivalent of toggling one of the buttons while (MOD) is lit.) Also, how would I adjust the “amount of impact” of the mod matrix assignment? (The equivalent of turning the MOD value wheel when one of the mod buttons is lit purple.)

is their a list of modulation values for this like shown on this page? Here is a list of 80 functions which can be modulated through MIDI parameters.

There is no external MIDI control of the mod matrix.

As you hint at it could’ve been done using Sysex, or even NRPN, but not via CC. In any case, it’s not implemented.