Unknown Netgear IP address on network (CG3000V2)

Primarily because of the ip address you mentioned (192.168.0.5), I doubt that it has anything to do with the router, and I suspect the common OUI is nothing more than a coincidence. Most routers have only two MAC addresses, one for each network interface (WAN & LAN), it is theoretically possible for it to have more if it is a wireless router, but in practice the wireless related interfaces will typically show the same ip as the router's LAN interface, or, if the router allows a guest network, an address in a different network range, so the x.x.x.5 suggests a completely different device.