Connecting to synced content on iPad from Apple TV

I'm away from home atm, and have a bunch of content synced to my iPad from my home server. I also happen to have an Apple TV 4 with me, and I'd like to play the synced content on the tv if possible.

I've selected the "share synced content" option on the iPad, but when I try to select a server on the Apple TV, I can see the iPad listed, but with "Needs Update" next to it.

I've tried selecting the Apple TV from the cast menu on the iPad as well, but that doesn't seem to work either.

My iPad plex app doesn't say there is an update (it's on 4.2) so is there anything else I can try, or am I stuck watching on the iPad?

Thanks!