Dominated by Lawler? Watch the fight again maybe. Imo Lawler won that fight but it was by a split decision, which was the right call. Anyways the fight ended with Macdonald on top smashing Robbie with punches/elbows, so dominated? No.
Rory becomes a better fighter after each fight, If Robbie and Rory fought again I wouldn't be surprised if Rory won. He's only 25.. Hasn't even hit his prime.
As for Brown, I don't think he will ever be legitimate title contender in Welterweight as of now.
Lawler vs Hendricks 2 is coming up December 6th, and Imo Rory should get the next title shot (Assuming he beats Saffiedine).
Unless the winner of Lawler vs Hendricks 2 sustains injuries that keep from him fighting for an extended period of time, the only logical next contender is Rory Macdonald. Not only logical, he's the only legit contender other than Lawler.
Woodley, Condit, and Brown still have work to do to become contenders, considering the latter two are coming off losses and Woodley recently getting dominated by Macdonald.