Once your offense goes cold after a couple of series, time to go to a 2-minute offense. You have to do something to get the defense discombobulated.
And I'd consider going more bunch sets (not spread out) - 2 TE sets or 2 RB sets just to confuse coverages. No more empty sets. Max-protect and get Dak moving to his right if possible. No more bootlegs (except maybe twice a game) since they've caught on to that. If their corners press, then have at least one of those receivers running a 9 or go route, if they line up deep off the LOS, throw quick hitters/hitches or WR screens and let Ceedee do his thing.
If they show, for example a blitz coming from the right side, Dak's throwing side, you should audible protection, pull them in, and hit Pollard on a quick hitter or forward swing pass, hit the go, quick slant, or quick hitter with Schultz.
If they persist on populating the LOS to stop the run, then I'd run 3 WR set the entire game and work the center of the field with Schultz. I'd add rub routes and trips formation with all three receivers on one side and Schultz on the other side.
Those are just a few examples.