Hello, thank you very much :)
Have you tried going the next day?
Viewing post in Bug report
I did not as I originally went there in the evening and had not done any work for him as of yet, I assumed it was something that would exist regardless of the day. Let me finish the fight sequences I am in and I will report back. Though I am currently about to fight with the half-demon, so I am not sure if that is going to change how the bug is presenting or not. Give me a few minutes and I will get back to you.
So I managed to get to the half-demon and lost that fight horribly. Advanced the day to evening and now Astaroth's work is available. Since I don't cloud save and don't have the game installed elsewhere I can't be certain if I experienced a one time issue in 9.1 or if it was caused by the fact that Astaroth was technically helping me up the mountain and now no longer is since I defeated the three knights and have the hammer.