He's in a pretty good position to win 2 of his 3 remaining games, so it would be good for you to plan on 2 more wins to win that cat. Thomas/Rask should hold his peripherals steady but I'm sure they'll slip a little with Ward so I can see his peripherals coming down a bit. Because he's behind in wins and you've got a ton of options left, he will have to start his goalies in all 3 contests which bodes well for you given that both the Isles and Sabres can light it up (the Isles moreso).
On your side, I would think Rinne will definitely get the start against the Wings and both Halak and Roloson will start at least 1 of their 2. Luongo will likely NOT start against EDM (too bad for your situation).
Given DET's goalie woes, Rinne's game is about as much of a sure thing as you have. I like St. Louis' matchups better than TB's, so I would probably roll Halak against CGY tonight while St. Louis' offense is still hot. My pick for Roloson would be MIN tomorrow if you need to start a 3rd guy. Those 3 could get you the needed wins AND peripherals. You'd still have Halak @ CBJ in your back pocket following those games if necessary. I'd stay away from Roloson @ CHI if I could though. Good luck!