Young blew away Brothers in the second half to score their most important win of the season.
The Cherrypickers came into finals off the back of three straight wins, but hadn't tasted success over a top three team so far this season.
However a dominant second half ensured they did just that running away with a 40-10 victory at Equex Centre on Saturday to go through to the preliminary final.
Coach Nick Hall is confident they are heading on the right trajectory.
"A loss couldn't be part of the plan," Hall said.
"We got our losses done early and with a short season we had to keep winning so I feel like we've been building all year towards this.
"But I still don't think we are the side and need to knock off one of the top two and compete for 80 minutes with them."
Young opened the scoring try as Blake Hewitt forced his way over after three minutes but it was Brothers who had the advantage after dominating field possession.
The Wagga side levelled things up as Dylan McLachlan scored off his own grubber kick after 14 minutes before Brothers fit the front seven minutes later after Edan Price scored off a short-side scrum move after a Nayah Freeman mistake.
Neither side could capitalise on a number of chances to see Brothers go into the break leading 10-6.
However the second half was a different story.
First Tom Jenkins turned defence into attack after going 90 metres after Mick Picker plucked a McLachlan kick.
Off the restart Kyle Richens made 60 metres before John Grant scored on the next play.
Grant had his second 10 minutes into the half as the ball bounced kindly.
With all the momentum Young made Brothers pay as Jesse Corcoran went over with 20 to play.
Tries to Jayke Hogan and Picker completed the route.
Hall was thrilled with how his team responded after failing to win the territory battle in the first half.
"We wanted them to turn around and start their sets from back there," Hall said.
"I didn't want them just to pick up a ball as we had played some footy at them.
"We also had some elements of luck, like Mick Picker pulling a ball out of the air, but people still have to push up and make them earn it.
"We made the luck, took the energy and the wind out of their sails by just being a bit more patient and going set-for-set with them."
Hall believes controlling the field position will be crucial in the preliminary final no matter who they tackle at Anzac Park next Sunday.
"Field position is important and that is the game Gundagai and Tumut do so well," Hall said.
"We were too happy to turn it over 30 or 40 out and next thing we are bringing it off our line but if we put it into the corner then we are bringing it out from a better position.
"It's definitely a field position game if we want to compete with the top two sides.
"We had to do that to win today and will definitely need to learn that to compete next week."