A question i always ask myself is, if we can see code on github for example, it still doesn’t mean their release has the same code right? They could actually compile their program with some extra stuff that sends data and just add that version on github release page, but the code itself would be clean on github right?
I’d recommend running pihole.yourdomain.com or jellyfin.yourdomain.com instead. I think using yourdomain.com/service might cause you some problems, that’s why i heard other recommend use subdomains instead.