Act 2 - Rathbreaker Bugged Out

The boss in early act 2. Rathbreaker, is broken.

Dying to this boss will not allow me to restart at the checkpoint, saying I do not have the valid quest state. I have the quest to kill Rathbreaker. I must exit to character select and hit play to respawn at the checkpoint.

If for any reason you walk down the ramps from his starting area, he leashes back to his starting point and becomes invulnerable and freezes. He does take damage, but regenerates at a very high rate and is unkillable.

This is a particularly annoying bug, because when the Hyena packs swam it is very difficult to deal with the spears and boss wind-slash moves. I reasoned, like other posts I've seen, that I could deal with the hyenas as soon as they spawn in at the ramps, but if I go too far the boss bricks.

I have had this happen a dozen times now and it is very un-fun. The first occurance was back in Dec around Xmas. Today I tried again and confirmed it is still bugged out.

And now I find out that if I waypoint back to Act 1, I cannot teleport back to Act 2 as for some reason the first waypoint in Act 2 simply dissapears from the map.

I talked to the Hooded One in Act 1 again, skipped the cutscene, but the instance is not reset in Act 2 so the boss is still frozen. I guess I have to wait for the instance to reset via timeout?

Is there another way to reset the instance that I am not aware of?