trying to play with roommate; "failed to find contact"

Having a weird issue. My roommate and I are both on Epic, on the same LAN, and our games apparently can't find each other. He's already on my epic launcher friends list, and we've played together before (back when the Epic exclusivity deal was still in place), but now when I try to add him as a contact in-game, it just says "failed to find contact". Help?