Thank you for your detailed explanation.

Sadly, there are some combinations of notes that iRp can’t be tricked into playing.

I made a test chart for Db7#11/G.
When I play around with the mixer, I can hear the G bass note

While in theory it is not the correct choice, you might listen to how iRp’s G7alt would sound in bar 7.

For the musician, you could write the “correct” chord name as an alternate which is ignored by the player.

Chord Test - Test


I'm sorry not to be of more help in this instance.
)BOB