Alright, so, as I understand it, you want to press on one switch on the Ground Control and have that load and activate a preset on the H9 and enable the H9 in the voodoo lab pedal switcher. You should be able to do that with program change messages. When the H9 receives a program change message, if a preset was saved activated, then it will load it as activated; if the preset was saved as bypassed, it will load it as bypassed.  And as far as I now, the voodoo lab pedal switcher also responds to MIDI program change messages…

If I'm misunderstanding what you want to do, please describe what switches you're pressing on what products and what happens now, and what switches you want to press and what you would like to happen.