With Nene out, KenMart has the better opportunity. Lee isn't getting the same minutes as he was before Zach joined the lineup. The various roles of the Knicks player are in flux (again).
On the other hand, Karl could sit Martin again due to his surgery recovery. Earlier in the week, the Nugs had a b2b and Karl didn't start Martin for the first game of the b2b. That really surprised me, as I thought he'd start Kenyon against the Knicks, and then sit him against Boston. Couldn't tell ya why, but the Nuggets have said they're not playing Martin in b2bs.
Bottom line, unless you hear Kenyon is going to start - try rotowire, yahoo!, espn, nba.com/nuggets/, or possibly the denver post and or the rocky mountain news sites - you start Lee if you're playing h2h. You can't afford to take an unnecessary zero.