The premiers struck first blood in just the second minute when Dave Tyrrell crashed through Jason Taumalolo for a soft try next to the posts.
Assuming goalkicking duties in Adam Reynolds' absence, Issac Luke added the conversion to give Souths a 6-0 head start.
But it didn't take long for Thurston to get the Cowboys back in it.
After setting up the Cowboys' last six tries in wins over Melbourne and Penrith, the champion No.7 laid on his side's first of the night in the eighth minute with a pinpoint crossfield kick for leaping winger Justin O'Neill.
Thurston missed the conversion and his errant pass 12 minutes later landed in the arms of Luke, who raced 40 metres clear to put Souths deep on the attack.
Inglis sized up the situation superbly to put winger Alex Johnston over from the very next play and Luke's conversion made it 12-4.
Inglis looked to have put the Rabbitohs further ahead when he swivelled through four attempted tacklers only for the video referees to rule he knocked on while trying to ground the ball for a try.
Steve Folkes and Steve Clark also denied Cowboys five-eighth Michael Morgan a try on the stroke of halftime for an obstruction in the lead-up.
Down by eight points at halftime, Thurston needed just eight minutes after the break to tie the game up, scoring 34 seconds after the interval and then slotting a penalty goal to make it 12-12.
Thurston's quick hands helped winger Antonio Winterstein to squeeze over in the corner as North Queensland hit the front for the first time after 55 minutes.
Thurston fittingly clinched victory when Morgan put him over seven minutes from time before hooker Jake Granville's 70-metre dash from dummy half earned the Cowboys their fifth try.
Thurston modestly deflected the praise towards his unsung teammates when asked if he felt like the best player in the world.
"That's for you to judge, not me," he said.
"I can't give enough credit to our squad. Across the park, our back five are taking some tough carries, the boys in the middle third are rolling off the back of that and it's a great team effort.
"I can't do it without those boys doing their job and they've done it extremely well over the last three weeks."
Souths coach Michael Maguire refused to blame Inglis' no-try ruling as an excuse after the Cowboys piled on 26 points unanswered points after that.
Maguire was more disappointed with "a lot of uncharacteristic efforts" from his premiers and singled out Thurston's try in the first minute of the second half, after Cowboys back-rower Gavin Cooper busted the Bunnies up the middle, as the turning point.
"It's amazing how one play can change a game very, very quickly," he said.
Compounding the Rabbitohs' woes was Ben Lowe being placed on report for dangerous contact on Thurston's legs, while Jason Clark was dazed in the second half.
- AAP
