Its no problem with both mouse and keyboard on the same USB port.
I use that via an external USB 2.0 hub on all my RPi's (1B/1B+/2B/3B).
This USB hub is however externally powered not to load the Pi, as my keyboard is backlited and consumes extra power.
I also run a PATA DVD and a SATA SSD on the same USB adapter via the cheap Ebay/AliExpress USB to sata converter cable.
The drives are also here externally powered.
1. Does Raspian recognize the USB dongle. I suspect a problem with the driver here, as these dongles are NOT standard bluetooth or WiFi types.
2. Use any cheap USB 2.0 hub with external power to ensure the Pi USB port is not overloaded. Any unused hub port can be used to power the hub via a male to male USB A cable, if the...