How to check/update dock fw when running a custom ROM topic

Having recently resurrected my TF101, I've found that the dock battery drains 1-2% per hour when the tablet is in sleep mode. Not bad, but not great considering my other tablet can go weeks in sleep mode with only its internal battery. I don't remember if I updated it to the latest. Because I'm running a custom ROM (KatKiss 5), there's no information in Android Settings that reports the dock version.

Maybe my GoogleFu has gotten weak, but I can't find steps on how to check or update the dock firmware from a non-stock ROM. I'm hoping someone knows of a way to do it from the command line (ADB or Terminal Emulator app).