The Dons, who finished top of the league table, face Workington on Sunday for a place in the final against Barrow at the Halliwell Jones Stadium on September 30th.
Cooke has been ruled out for the rest of the season after breaking his kneecap during last week’s 22-20 defeat against Raiders, but has backed his team-mates to progress.
He said: “It’s been a very enjoyable season for me coming back after a while out of the game. The lads at the club have been fantastic and to win the League Leaders Shield was a great achievement for all the people involved here.
“We’ve been the most consistent team all season and we were disappointed to be pipped by two points last week. We want to make amends for that by taking on Barrow again in the play-off final and ending the season on a high.
“The fans have been brilliant all season right from the first moment I joined the club. There is a very loyal and passionate core set of fans and hopefully we can begin to see more faces coming to the games next season as this is a great club with great facilities and ending this season on a high would be a great way to encourage new fans.
“Winning the final would mean everything for the players and especially all the people who have been with the club through the tougher times in recent years. We’re very disappointed with last week and winning the trophy would be just reward for the excellent season we have had.”
Doncaster have already secured their place in the Championship next season, alongside Grand Finalists Barrow, Workington and Whitehaven.