Gortash Netherstone missing

[Butthole Baguette]

I've reloaded earlier saves and still, he will not spawn with the netherstone I need to continue the campaign. Does anyone know a workaround? By the time I realized it was missing, i'd invested way too many hours to ever dare to go back : (

EDIT: Nevermind, I am a potato - Wyll had it in their inventory, I swapped them out not long after I killed Gortash