If the Rams can't get by the Cards & 9ers without TG they probably aren't going to go too far in the playoffs regardless of seeding.
Their hopes from here on out are more related to defensive consistency than anything else. If the defense can make the required strides we'll win those two games and go into the playoffs with a healthy Gurley. If not, I still wouldn't want to risk our star RB vs two division scrub teams. Rest him.