No Line of Sight?

I had an installer come out last week who mentioned to me the dish the previous owners had would not work anymore because of some tree growth. He said to give him a minute and he got out his tools and ladder, went up to the roof came down and told me he could do it but needed the right note from my landlord. I called back, next installer came, took a look in the back while on the phone with his wife/girlfriend, came in and said he 'can't do it', 'it's not gonna work'.

I understand that a dish will NOT work with trees in the way, i'm not trying to be unreasonable here. My question is should I push to have someone else come look? I just don't understand why the first man would say he could, and he actually tried... if it' can't be done?

Sorry i'm just really dissapointed.

Thank you all so much. Really.

-Jacque