Please explain who "handed you this project"?

I'm just confused why your company would be bidding on a Crestron system if they are not Crestron dealers?

To answer your questions. 

- Yes

- LAN

- The amp is just a mutli-channel amp with line-level inputs

Every product you show has publicly available manuals, but installing and setting up a crestron system, espeically programming one when you have zero expereince wtih crestron is big reach and will probably result in failures.