I don't think you've mentioned where you're at but if you're within a few hours of Upstate SC I could pull the tune for you. I feel like you would get a similar offer if there's another Goblin with HP Tuners in your neck of the woods. It's free to an owner of HP Tuners to pull the tune and do a quick comparison.
P1133 is for an O2 sensor, but because it's not accompanied by a rich or lean error code, I'd guess first it's a bad O2 sensor rather than you having put the wrong fuel in it. Combined with the P2135 code for the throttle body, it's not surprising that it'd run rough.
Don't put too much stock in the "Stage 3" description, there's no set rules for what makes mods one stage or another (outside of what a specific vendor will sell you as a package with their name on it). For example, there was a GM Stage 3 that also deactivated AC. It can be argued that all LSJs need a dual pass, which is easy enough to install after you do your teardown, but I think it's a little silly too to suggest that a 2.8" pulley needs cams.