Is killing the Prince in Sahuagin city the only way to obtain these gauntlet? Can I help the Prince and the high priestress and still obtain these gauntlet? Is there a way to complete both quest? Can I hurt a monster only touch by +4 weapons with these gauntlet?
Please answer a.s.a.p. Thanks in advance.

Yes. No. No. No.

No Problem

I heard you could pickpocket the gaunlets off him. Worth a shot if you don't want to kill him.

I try yesterday to pickpocket the king but I didn't get the gauntlet. Buy I found the treasure room key and it's was pretty cool. I've got 2 rod of Lordly might now.