Montreal doesn't have a top six. They have a collection of 12 forwards not playing to their ability due to bad coaching and a negative environment created by their former general manager.
Until he gets sent down he should be playing ideal minutes against weaker lines. Get him on the top powerplay. Get him against other teams fourth lines. Set him up for success not failure.
I'm sure he will still get some PP times, and he probably will play now against other teams forth line instead of always facing top competition like he did with Suzuki, which hasn't been working this season. Ducharme won't put two rookie together on the same line (Poehling and Caufield) since most NHL coach are conservative on that point, and is Dvorak that much of a better center for centering for Caufield than Perreault? You said it, montreal doesn't really have a top 6, we shouldn't focus that much on his position on the line-up, let's wait before judging his ice-time utilisation, even with Suzuki, he player less than 13 minutes in the last 2 games. Probably won't get worse.
Not a fan of his utilisation either since the start of the season, but playing against weaker competition with a vet center might actually help him get back on track.