Path of Ascension is broken. Upon defeating the scenario, it says collect your reward. After collecting the reward you talk to the NPC in the area who either teleports you to the top (counts as a defeat), or teleport out (doesn’t register the victory). It will not advance the difficulty up ever after killing each boss with each of the three soulbinds.
I have max sanctum, max renown, all quests completed with all the different fights collected. I have done interface resets, disabled all addons, submitted tickets, etc. The path of ascension is simply not counting victories.
This is pretty frustrating as it is tied to quite a few achievements as well as mounts, pets, and transmogs.