Good morning Cliff
I'm afraid I'll have to pass on the Violet Picture approach procedure - was 38 years ago for me and my memory is no patch on yours. No notes to refer to either, about all I can recall is also using it to home on SARBE emergency beacons as well.
This site
Q - Code Information Page lists QGA as Unassigned. Perhaps too good a weekend in Ponca City prior to that class Cliff.
Love reading your experiences.
Edited to add perhaps the use of QGA was for local training purposes/reasons.