Replace the pilot-derived RDS path with a PiFmRds-style 228 kHz shaped biphase generator, resample it into the composite loop, and retune Pluto example levels plus spectral thresholds around the new RDS behaviour.
Drive RDS in the offline/MPX path from the pilot-locked 57 kHz carrier with biphase symbol timing, and adjust Pluto example levels plus spectral thresholds for the new multiplex behaviour.