Well, it does look like amp'd is using a cdma system. Also from the coverage map it looks like they might be using the verizon system as a host network. If I am right amp'd would be a 3rd party dealer. They would be responsible for tech support, billing and collecting, the "host" would supply the service and supply the 3rd party dealer with equipment.

The verizon equipment is unlocked however, that does not mean that amp'd can use an unlocked phone, or that they will activate one. The best way to find out for sure is to contact amp'd and ask.