Stewart also has an ankle injury and is questionable for Monday
As talented as JStew is, it does no good when his O-Line is garbage, the OC has no clue how to fix what is broken, there is little to no leadership on that team, the locker room is blowing up and guys are starting to point fingers at each other, the GM has already been fired and the coaching staff is likely out the door at the end of the season. They have taken on an "every man for himself" mentality and the guys with guaranteed contracts (like Stewart and DWill) if there is any question whether to play through an oww-ie or not, will err on the side of "why go out there and get killed and take a chance on a more serious injury?"
JStew is still one of the good guys on this team and he does not have an attitude like DWill - but with the O-line in shambles as it is I just don't hold much hope for him to produce anything more than average Flex numbers the rest of the way. In a PPR he might leak up to low-end RB2 - but set your expectations accordingly.