Your estimate for the speed of light is wildly off. The speed of light in a vacuum is 299,792,458 meters per second. The speed within the fiber cable or coax is considerably slower than that. Typical coax might be 66% of vacuum speed.

The time is going to be taken up in the various gateways and routers. Perhaps also in retransmissions. 80ms is so incredibly slow for a remote DB, that this is for sure a major problem. My home PC pings google in 13 ms round trip. A well-configured local LAN is going to be much faster than that.