First one isn't likely at all, given Jones length and DC's lack of.
Second one is definitely possible, even with their frame differences I would bet that Jones is a lot stronger in the weight room than DC, and to go with that he can actually use that strength via his leverage and wrestling skill.
Jones outwrestling DC would surprise me, but not stun me. He took it straight to Chael, but DC is at another level. I think Jones will be able to keep up, but if he dominates DC at his own game, I would be pleasantly amused.
Rashad and Jones showed that Chael's wrestling is really only impressive against guys that don't know how to wrestle. I'd rate it a little lower than Dan Henderson.