The runner-up also qualifies for the $500,000 final at Randwick on April 6 with La Scopa now at $4.50 to win.
“She's been stakes-placed and won a Highway race so she deserves her place ,” Dunn said.
“She got into this race well with just 54 kilos.”
Collett admitted he had not been as confident on the turn as her odds would have suggested.
“I've been more confident,” he said.
“She was on the bridle then off the bridle and ran the race in patches. But she's the right type of horse for the final. She ticks the boxes.”
Daniel Bowen, trainer of the runner-up, said Queen Of Kingston had improvement to come.
“This is the biggest thrill I've had in racing,” he said.
Horses from all areas nominated for the series have the opportunity to run in the Wild Card.