For these questions I search d20pfsrd to figure out where something is from. So on wiki page for
Grand Inquisitor it has a copyright 15 section at the very bottom of the page.
So its from "
The Secrets of Tactical Archetypes" from Rite Publishing. If it was from Paizo I could easily then tell you which addon. With the 3PP its a little harder.
I am pretty sure AndrewD works for Rite maybe he can answer if this one was entered into HL or not yet. I know a bunch of Rite stuff was.