@crinrictI did not try the cauldrons in the magic realm in that game session. Unfortunately, I did not save the game. I did go to the previous save and my sim was able to brew potions. I was unable to open the spellcaster perks however and I am not sure why since I did add them. I went back to three previous saves, and in each she was able to brew potions, but in every one the spellcaster perks is greyed out. They were not always that way. I also tried brewing potions in the magic realm in the previous saves and had no problem. It seems that whatever went wrong happened after I added the perks.
I did see another post regarding the bloodline trait and the problem with the perks, My Sim does not have that trait and I am playing with an existing family that I have been playing with for about 8 months and she has never been any other occult form. She is a celebrity though.
Edit to add... I was curious to see if the fame points were affected so I checked and she can no longer access her fame points either.