Two runs ago (that ended with wormy death), the triggers all worked correctly. I posted into #speedrunning of the Discord that file set with instructions on how to get it working. My last run the "Wormy Knows Final Boss Died" didn't trigger, making the Wormy death split hit the second to last split instead.

I've removed the split from my local (deleted the split entry in LiveSplit and set ModPrefs -> FinalMiniBossDefeated=0

On my last autosplit run, I can detect game start (when player has finished loading), Tutorial boss defeated, Boss gauntlet entered (for tripod, this is just the tunnel), boss's entrance area opening up, boss killed, boss exit wall dropping (currently labeled Boss Despawned), and the code behind final boss defeated isn't working right. That trigger appears to be final miniboss defeated.