Yes, that's exactly the problem, without his weapon, he can't use some of his abilities.
I can't give him a weapon, it's not possible, when I try, it says "You cannot modify this companion's equipment".
Well, to explain myself properly, what happened exactly was that there was this button that said "Reclaim inventory items" in the companions & contacts window. I didn't know what it does, so I tried to click on it. It moved all his gear into my inventory but at the same time, there was probably some kind of a visual bug, because I could still see him wearing all the gear. So I thought it duplicated somehow and threw all the gear in my inventory away. Well, that was a fatal mistake, because next time I logged in, the gear on Gault was gone as well. And that's how I got into this situation.
And I have entered CS ticket already, explained everything. I was able to retrieve his gear back, but it's still in my inventory, so I can't put it on him. After that, all they told me is that they suggest I find someone to help me get through the chapter and make a group or something, that's why I am posting here....