IMO, DC makes Jones look silly if they fought. I think stylistically, whatever Jones can throw at DC(besides the reach), Cain already throws at DC on a daily basis during training. DC's explosiveness and ability to close distance are both top tier, and (specifically from the Gus fight where reach and height were near identical) I see those as being huge threats to Jones.
DC regularly trains with a guy bigger than him(Cain) with superb wrestling. Come fight time, DC will have regularly trained with a guy MUCH bigger than him(205 vs 250) with superb wrestling.