MODX to instigate a snapshot Programme change on the X18 X Air

I am using the following setup

x18 mixer with the X-Air app on the Ipad
Ipad running Camelot Pro
Native INstruments A61

Set up

4 port hub plugged into the IPAD
A61 and MODX8 plugged into the hub
Midi CAble (5 pin) from MODX out to X18 Midi in.
Microphone into X18

I have 2 main snapshots

1 - vocal mic is sent to main output
2 - vocal mic is removed from the main mix and re routed to the MODX AD input 1 via Bus 1 which then treats this as the source for a vocoder

Camelot Pro is doing a really good job on controlling the programme changes to the modx and also acting as a bridge for the A61 to also control specific channels.

Camelot pro also allows for midi programme changes, which I know the x18 can accept.

The reason for the request is that i am I do not want the vocoder on all songs, however when not used as a vocoder I need the same mic to act as a standard vocal mic.

I could potentially have 2 mics and remove the vocoder source from the mix however the Idea would be to have the single mic covering both jobs and when the song is chosen in camelot pro, the programme change would change to the relevant snapshot./

Can anyone help.