Griffin was sacked in January for allegedly breaching his contract by making unauthorised appearances for Morley Rugby Union Club.
The case went to a Rugby Football League tribunal this week and the 36-year-old says he was cleared of gross misconduct, serious insubordination and breaching his contract by playing for another club without permission.
Rovers confirmed the tribunal took place and are now understood to be deciding whether to appeal.
“There’s three people on the tribunal, a judge and two others and their decision was unanimous,” Griffin told The Yorkshire Evening Post.
“We have two weeks now to come to a compromise agreement for a settlement and loss of earnings.
“If we don’t, it goes back to the tribunal and the judge will settle it with what he thinks I should be paid out.”
Griffin insisted he had permission from Rovers to play for Morley.
“They didn’t do things by the book, thinking they can do what they like,” he said of Rovers.
“They tried to make out I did it without permission.
“I played under my own name, my name was in the programme and I went to a local club 10 minutes down the road.”
Griffin has yet to find a new club in rugby league, but has continued playing for Morley.
He said he was “committed to one last year” with Rovers before hanging up his boots.
“I’d like to stress, I had two really good years at Featherstone,” he said.
“I really enjoyed myself, I played with some great players and we achieved some good things.
“I worked with a good coaching staff under Jon Sharp and I played something like 67 out of 69 games when I was there.
“There’s some wonderful people there, a lot of volunteers and the fans are great.
“I wish them all the best, I hope they have a good year and I am just upset it finished the way it did.”
Before joining Rovers Griffin had spells with Wakefield Trinity, Huddersfield Giants and Salford Red Devils and was a Leeds Rhinos Grand Final winner in 2012.
Rovers issued a statement after being contacted by the YEP.
It said: “The club and its legal representatives attended a Rugby Football League tribunal on Tuesday.
“The hearing was called by representatives of former Featherstone player Darrell Griffin, who parted company with the Rovers in January.
“A decision was made following the tribunal, though the club and its legal team are yet to receive evidence to support it.
“Once presented, Rovers officials will decide on their next course of action.
“Until this time the club will be making no further comment.”