Try clearing the game cache or reinstall if you're unable to talk to Parry, who ends up over to the Left of the screen.
I remembered from the first run of this Event, the tortoise was up by the armour when vanquished, but this time I never saw it either. IDK if I was distracted or if Pixel changed something & the popup covered what was happening. Either way, I still got to talk to Parry over where he was fighting Mordevolt.
EDIT: I played the mine again in my other account & DID track the tortoise from the lower RT corner of the courtyard & up the hallway. Saw Parry vanquish him before the pop-up. It all went pretty fast, especially if using the speed potion to clear tiles, like I did on the previous account.