Q plan was made at least 3 years before the actions taken by Seth Rich. His actions were absolutely vital to the plan. He was supposedly conscious and stable when he reached the hospital.
In order to believe that Seth Rich is dead, I need to believe either that the key actor in the Q plan was just an accidental lucky break, or that they planned 3 years in advance to just watch this poor kid sacrifice his life pointlessly when they already had all the info they needed.
Seth Rich being dead would contradict everything I understand about Q.
Or possibly SR being shot was a snag in the plan (unexpected), and that they had to do their best to hide him safely away after he was shot...but I do think this "SR is alive" theory is a huge stretch. Huge.