They has comms all the way to the planned OP. There is no technology that can penetrate mountains. If the geography dictates it, you have to plan relays to support your positioning. The movie hinted at that through the incredulity of the higher commander who could not believe that the planned status updates had been missed and yet not reported.
there was that failure, too. Probably the worst. The radios should’ve worked on the summit, that was what they all were counting on.
I missed the message of the conversation between the Captain and the LtC.
do you mean the captain was outraged as opposed to incredulous?