the protector stone is bugged anyway even without the min dmg jewel. The 28-30 damage is working but the ED won't be applied to your overall>
I have a -10 stone in my helm just for the -res/high mf. I don't think you screwed up tbh.
going to get another on ladder and put min max rare when i get one then ty very much for the info
im using it for the same reason as you, that -10 is amazing for me in p8 tz with an edmg bone break