Metal roof install

okay heres the situation i had an installer come over on august 26th to install direct tv, and he came over and it looked like everything was going to be fine.  i want this service because of the sunday ticket and because i want to get away from cable.  anyways after about 15 minutes he walks up to me and informs me that i cannot recieve satellite at this location because i have a metal roof.  I have a spot on the balcony where the roof is even flat that they could install there but no he says he has nothing that could drill through metal roofing.  and he also says its hollow underneath?? i dont know what thats supposed to mean.  i dont know alot about roofing but i know its not hollow.  I have seen dishes on metal roofing before and i was informed that they could install on metal roofing.  And also he was pointing west for the line of sight and said i couldnt put the dish on the ground because i have trees in the way.  i have a clear veiw of the southern sky all my neighbors dishes point the say way i thought mine should face, S-SW.  anyways i have another appointment set up for septemeber 6th with another installer.  Does anyone have this service on a metal roof or was he just being lazy (which is okay if he was being lazy id rather have it done right then just thrown up there).  Anyways any thoughts or ideas would be helpful or any stories to share about metal roof installs for direct tv would be greatly appreicated.