When TM took off running, I believe GZ did get out of the car and try to follow behind TM to see where he was going, to "watch" him .... I don't think the verbiage is as important as it's being made out to be. When the dispatcher said, "we don't need you to do that", GZ said "OK". For me, the "OK" is more proof that he stopped following than anything else we have.
I believe GZ had the utmost respect in law enforcement, and so he obeyed the dispatchers request and headed back to his truck. Bringing up the incident 7 years ago when he had an altercation with a plain clothes officer will surely be the answer to that statement, and it doesn't negate everything he's done, consistently, for the past 7 years.
JMO