But Croker's 77th-minute touchdown tied the scores up.Canberra were the better team in the extra time period and an Aidan Sezer field-goal attempt hit the upright.
Soon after, Wighton passed and his former Country teammate Aitken took an intercept.
Canberra dominated early in the match and had a try denied to Joey Leilua in the eighth minute. After that, the Raiders struggled to control the ball and mount any pressure on the Dragons in one of their worst halves of football of the year.
Tyson Frizell broke through a disjointed Raiders line to score in the 17th minute and put the home side ahead 6-0. Those were the only points of the first stanza.
The main talking point of the first half came when Joel Thompson hit Blake Austin with a high shot and broke the nose of the Raiders' playmaker.
Referee Ashley Klein declined to award a penalty claiming he didn't see the high tackle.
Then, to the bemusement of Canberra, the bunker then declined to rule on what was obviously a reportable offence.
Dragons coach Paul McGregor praised the resilience of his side.
"It was nice to be on the end of a win like that. We haven't had much luck this year so to get some tonight in front of our home crowd was great," he said.
"We were very committed tonight. Defensively again, we were on song.
"We are in the eight now with a five-five split and, all the travel, we have already done that."
Dragons skipper Gareth Widdop struggled to believe the ending to the game.
"It came from nowhere and lucky Euan was on the spot and he caught it," he said.
Raiders coach Ricky Stuart defended the performance of Wighton.
"He is disappointed but he got us back in the game with a magic pass to put Eddie away (for Croker's try) so ..." Stuart said.
"When you touch the ball so many times, you are going to make errors and be a hero. We are all supportive of him - those things happen.
"We did a wonderful job to get back into the game, without playing our best. But we beat ourselves again."
