I think that's possible, as well. He's still 70, so his inherent physicals wouldn't be much better than in AotC/RotS, and his augmentation somewhat weaker. Maul has a genuine chance of tiring him out.
However, he's still implied to be the strongest student in Yoda's Jedi history, including Mace Windu, whom Dooku is at least a rival of. Swordsmanship-wise, Dooku has him outmatched, and Force-wise, Dooku has him outclassed. However, all of the physicals side with Maul, so I think this should be a challenging fight for whomever manages to come on top.