@stephenrobles I’m sure I’m telling you junk you already know, but, just in case

If you:

1) start YT on the Apple TV
2) start a video on the iOS app
3) use the cast button on YT on your phone
4) you should be able to cast it to the TV, in a more hand-offy way, not an air-droppy way

Not exactly what you’re asking for, but pretty close.