Gulzal, the Living Furnace + Rhoa Mount bug

Using the Rhoa mount during the Gulzal boss fight, I ran down the corridor attacking while he followed after. When he reset to run back to the lava and trigger his lava flows attack, I ran faster than him and passed in front of him. After passing, he turned around and ran back down the corridor and spent the rest of the fight unable to change phases properly while constantly running back and forth without attacking. At one point he ran passed me, but I ran back in front of him again and he turned back around.