u/Coltrick3

I’m playing fallout 3 for the first time and I’m working on the Outcasts intro quest where I give Casdin technology. I’m holding 2 power armors and power helmets that I took off of some corpses in the super mutant bunker by the national archives but he won’t take them. I looked it up and I haven’t found any mention of this or reason why he shouldn’t take them. Am I doing something wrong or is it ok to just sell them for caps?