Same is happening to me, the principal never showed up to deliver the diplomas, at first I thought it was a glitch so I erased the last save the tried again, but the principal didn't showed up again, I looked in my game and she is dead, but I dont know how to assign a new one, and thus the photo never appeard in the inventory
The High School Years jobs are in fact hidden traits assigned to sims. You can assign a new principal by:
You can now switch back to your original household (not recommended to have principal in active household). Remember to “protect” your principal from Neighborhood Stories accidental deaths.
An alternative way if you don’t want to use a cheat is to make the game generate a principal by going to school with a teen during school hours.
Both of these methods are cumbersome and require the player to check if the principal is dead/alive BEFORE the ceremony.
Hopefully it can help a few simmers like @AlexEbertRo7 who have a save before the ceremony and are wondering how to get a new principal.
