Hi Kroth and welcome to the forum. I'm so sorry to hear about your brother in law...how sad and he is so young which makes it worse. You and your husband are so kind to care for him. It is stressful, I'm sure.
Where is he being treated? I do agree with Christine, is a second opinion something you can do? Again, you may have already done this but I had 3 opinions until I felt comfortable with my treatment.
Please keep is posted..I am thinking of you and your family.