E.B.
It seems like the gifts you have mentioned are quite prominent or visible, when one walks into a room. You can see the blanket, the pillowcase, and it's quite apparent to the casual visitor that this kid was in a sport. So maybe the dopp kit seems too private or personal to the other mom. Toiletries usually go in a shower caddy, or in a bathroom cabinet, and maybe the other mom realizes that although it would be a nice gift, it's not "visible" enough.
So, thinking about visible things, things that would make a friend say "oh, you were on the ________ team", how about a personalized (engraved) coffee thermos or high end water bottle (not a cheap plastic one but a better one), or a masculine type of photo frame, something for their car (if both guys have a car) like a seat cover in the school colors or a license plate frame that's customized? Or, get a great photo of the two of them (or their whole team and coach), and photoshop it to look like it's vintage (sepia tones) or make the photo into a sticker for their laptop or make it into any one of the photo gifts that Costco and places like Shutterfly offer.