I'm replaying TES: Oblivion GOTY in 2015 because I'm a PC noob and I wanted a direct comparison with something I played on a console. And because it's a good game.

At some point I remembered this untracked quest and started collecting skulls in the SI. I was able to collect four of the five skulls. I am missing Salonia Viria's skull, which I should have found in Cann: Amphitheatre. Probably did find it earlier and dropped it. Or put it in some corpse's inventory when overburdened. Anyway, it's missing. And it bugs me that I can't finish this quest. (Not as much as being unable to buy Rosethorn Hall because Shum gro-Yarug fell off a bridge my first time through, but ...)

Would any of you experienced and resourceful players happen to know a way around this? A console code perhaps? I've looked, not successfully. Thank you for your time.