He says he's not allowed to "work" on a metal roof, saying that's Dish policy. Some installers are saying it is allowed, while others are saying it's not.
As the OP later added, it's a metal roof, three stories high, and a steep angle. No doubt every other installer would give it one look and say "No LOS".

As is standard operating procedure, it would seem, get a 2nd installer out and he'll say "no problem".