See the note below from the TI C2000 User Manual on how to access ADCB channels on the 28069. You should not use a separate component for ADCB. The Coder treats the 28069 as having just one ADC (ADCA) with 16 channels, and will generate an error if you try to include a second (ADCB).
Also note that you will most likely have difficulty running this model on the 28069. This model was designed to run on the 28379D. The 28069 processor is significantly less powerful than the 28379D. You will have to make some simplifications.