The first time Gale talked to me about his condition was about the Idol of Sylvanus in the Grove. I turned him down since I didn't want to piss off the druids.
Now I have the Staff of Crones and Amulet of Selune's Chosen. I thought both would help him. I'm not getting any dialogue options to give them to him. Tried talking to him in camp. Am I supposed to wait until he brings it up again? Haven't tried having him in my party and talking to him while exploring. Or maybe it's a bug?
I hit that same bug; he wanted the selune's amulet and then once he consumed it he asked for it again, eventually he would take the sword of justice but has never taken the other weapons from the like the hammer and mace that are also blue. sorry can't remember the names right now.
The bug crew can have a look at your file and see what's up.
Cheers