I mean, when your center and LT are not only backups but
3rd teamers (Shelton and Jackson) you're not going to blow defenders off the ball... Not that they are just going through the motions but difficulty running the ball should not be a surprise there. Personally I'd have started Noteboom. I think he can use 75-90 preseason snaps. But it is what it is. See what they have in Jackson and try to get him onto the PS.
I actually think while they'll keep scouring the waiver wire the Rams will ultimately end up sticking with what they have at RB. McVay likes Jones. Funk (mainly a special teams guy) has held his own so far for a rookie. Calais is mainly around to return kickoffs and (possibly) punts.