The frequency of the signal being sent is the key.
The lower the frequency of the signal, the deeper it penetrates the surface of the wire.
For Video frequencies, the depth of penetration is rather shallow, so plated wires work fine. For Audio signals, the depth of the signal into the wire surface is DEEPER than nearly any plating, and solid wires should be used in hi-end applications. (when the signal has to move through the plating/core it will add distortion to the signal.. in theory)
A digital signal is probably near the video frequencies, so a plated wire 'should' be ok. However, with the BIG DEAL about 'jitter' I would use only a 'solid' or nonplated wire.