I don't think that he could do it. He's very athletic for a defensive end, but he's over 280 lbs and probably not capable of doing much in coverage. If you rush him all the time, then it's a 4-3.
Of the free agent defensive lineman, the only one worth big $ imo is Haynesworth. Put him next to Stroud with Williams to provide occasional relief and you've got a defensive interior that can take you somewhere...