The manual doesn't mention this radio.
The FT-100, per manual, is a 6 pin modular connector microphone that uses a similar wiring as Yaesu FT8800/8900. The microphone pinout follows the same wiring of a Yaesu 8800/8900, so you should be able to use same jumper configuration in RR radio. On the remoterig radio settings page, the Yaesu FT-100 COM0 baud rate is suggested to be 64000, similar to Yaesu FT-857. It is program mode option 16, the last one in drop-down.
I have never owned the FT-100, but I do have the Yaesu FT2600 and am familiar with this type of mic wiring. So I'm sure this should work, but do at your own risk.