RE: JR9303 & Buddy Box
1. This looks to be an error in the manual or it is just a matter of confusion of the wording, this is not correct. All functions are controlled by the slave when control is given to the slave. The slave TX must be fully set up for the model.
2. It will work fine assuming that you set up the mixing in the 8103 to set up the model fully on the same channels etc.