While Matt Hamill did say he could not continue (because of his shoulder) after the fight was stopped because of the illegal elbows, it was stopped because of the elbows! Its pretty simple!
The illegal elbows stopped the fight, Hamill could not continue. The only option then is to DQ the fighter who caused the fight to be stopped because of illegal elbows.
If Jones did not throw illegal elbows there is no question he would have won that fight, but one must follow the rules when Maz is the ref!
The fight was stopped because of the elbows to inform Jones the elbows were illegal. But the fight didn't continue due to a shoulder injury. If there was no shoulder injury then Matt could have potentially been given time to recover and continue the fight.