This is what I ended up doing with my roast, just in case anyone cared.
I rubbed salt, pepper, and onion powder all over each roast (I used 2 - there are 6 of us here and one of those is a teenaged boy... lol) then browned them on all sides in a little bit of olive oil. While they were browning I cut up 2 onions, a couple of stalks of celery, and a couple of green onions. I put the browned roasts into the crockpot then added the onions, celery, and green onions to the hot skillet & cooked them until the onions were limp. I then added a few shakes of soy sauce, a smidge of worcetershire, and one box of Swanson beef broth. Once it had heated through I dumped it on the roasts then cooked it all on low all day. I considered using a small bit of cornstarch to thicken the juice, but in the end I just left it as it was - more of a jus then a gravy.
It was mucho delicioso! I think this would even qualify as a phase 1 dish esp since I opted not to use the cornstarch, right? Also, sodium content could easily be reduced by not using as much salt in the rub and using low sodium soy sauce and beef broth. I served it with sauteed onions and salad. I almost made brown rice (I'm on phase 2), but in the end I forgot until it was too late.
Anyway, there it is for anyone looking for a decent roast beef dish that's SBD friendly.