Are you sure you don’t mean MIDI CC change? There is no tuner preset on the H9. It has to be engaged sending a MIDI CC# and you can actually customize which CC# to use. Maybe there is a conflicting CC number being used that is causing the problem.
What PC # is Preset 1 on the G3 sending?
What commands do you have programmed on the G3’s Preset 9? Again, this should only be sending a CC#. Check if the toggle behavior itself doesn’t have programmable latching behavior, meaning it’s in a different instance with every toggle; some controllers offer this functionality.
By this statement, the G3 is sending a PC to the H9. Make sure there is no other command being sent.
This would be a good time to use the G3 App to make sure your not missing something.