I think that if Randy is still strong enough to take Tim down and pass guard, he'll have an excellent chance. But that's going to be tough with Tim's reach. Even if Tim decides to jab-jab-jab for most of the fight, Randy will have to be very careful not to get caught going for the big shot. All it will take is one big punch from a huge guy like Tim. Chuck only needed one.
I'll be rooting for Randy in this one, but I suspect he'll hang for five rounds, give Tim a much more exciting fight than Monson did, but still lose a close decision.