Lipo rider plus -- accessing charge state?

I’ve been working on a project where the Lipo Rider Plus is being used to power a microcontroller. I’d like to access the charging state (whether the Lipo Rider Plus is actively plugged into an external power source via USB-C) so I can illuminate a “charging LED” from the microcontroller. I had thought the VUSB header pin would provide that, but I realize that it reports 5v regardless of whether external power is provided. Is there any way to access this state from the board?