I purchased Seasons Pass to watch soccer matches and it works just fine on my Roku TV but no matter what I try (logging in and out, scanning with my iphone) I cannot get the app to show up on Apple TV on my Samsung Smart TV. Help?

2018 Samsung TVs from the UDH 7-series should have the Apple TV app with all the services that go with that (Apple TV+, MLS, iTunes Store movies and TV shows for buy or rent, other in-app premium channels).

List of Apple TV app-supported smart TVs and third party streaming devices - Apple

Try finding MLS on the Watch Now page, where you’ll find both the Channel icons and other promotional tiles.

Else try finding MLS through Search, where it should be listed even before entering a search query.

Verify that the TV system software is up-to-date.

Verify that the Apple TV app is up-to-date, preferably through a setting that keeps all your apps up-to-date automatically.

Apple TV app user guide for smart TVs and third party streaming devices - Apple Support