Copper won't provide any electrical isolation/surge protection unless properly grounded. This installation is going to be an exposed cable laying on the ground for the full run. It is also in a very high RF environment that is producing lots of harmonics, digital transmissions, which will wreak havoc with an exposed cable. Fiber is the best choice and has, basically, no bandwidth limitations to boot.
Unlikely, very, very unlikely. He likely has more invested in the amplifier than his entire camera system. Not to mention the other equipment, towers, beams (antennas larger than your car).
Fiber is the best solution as the copper will just act like a huge receiving beverage antenna.