Update on system problem:
Measured my voltage at the battery posts and power wire connection to battery and I'm getting 13.9-14.2v idling. Went around back to check the power connection to the amp and ground and I'm getting 0.1v.
So I start scouring through my car up and down the power wire trying to find a laceration in it. I don't find anything other than a few scuff marks in the plastic, and then I get to the fuse. One of the bolts inside the fuse holder has came undone by about a quarter inch and the other by about an eighth. The fuse is barely being held in place. I'm about to go back out and fix it now. Hopefully, this will fix my problem as a whole. I don't see what else could be preventing me from getting any power at the amp end of the power wire but a full 14 at the battery.