Apple TV: Air Play works, iPhone Remote App Doesn't

ok, i have two apple TVs, a version 2 and a version 3. i have an iPhone 6S with the remote app. when using air play, the iPhone sees both apple TVs and is able to air play content to both.

the remote app, however, only sees the apple tv 2 and not the apple tv 3.

i have tried reinstalling the app, rebooting the apple TVs and even putting them on the same network (i have an apple airport extreme tower with a regular and a 5GHz network - the apple TV 3 is connected to that, as it is right next to the AP extreme. the other TV is in the basement, so it works best with the non-5GHz network). in the past, both have worked with the remote app, despite being on different networks. now i can only see the basement apple TV.

any ideas?