Since the most recent Shield TV update the BBC iPlayer App keeps removing its self from the UI. It even removed its self while I was watching it!!
I know, I know, I'm in Ireland and have location turned off and language set to English UK. It was working fine and didn't disappear until the most recent update.
When it's there, it works fine! But it's weird that it disappears (and even more so, to do it while I was watching it!)
Weird. It's figuring out your location some how, which is why it's being hidden from the launcher. Which I am sure you already realize.
Maybe try sideloading the app.
I sideloaded it a while ago so I could use it here in Canada. Never disappears and I don't have my language set to English (UK) either.
I upped it to my dropbox for you if you want to try it.
https://dl.dropboxusercontent.com/u/59838331/BBC%20iPlayer%201.1.58_58.apk