Gianni Paladini told Blackfriars Crown Court the men punched and threatened him and tried to force him to resign at gunpoint, before a home game in August.
In total, six men faced charges of conspiracy to blackmail, false imprisonment and gun possession.
Last week, two club shareholders were cleared and on Wednesday the judge ordered the jury to acquit the others.
Mr Paladini, 60, told the court he was forced to sign a resignation letter after being ambushed at gunpoint at the ground in Loftus Road, west London.
Queens Park Rangers shareholders David Morris, 50, from Buckinghamshire, and John McFarlane, 39, from west London, had denied all charges.
 |  It has been a traumatic time for the club  Tracy Stent from the QPR First Supporters' Trust  |
The other defendants who denied all charges were: Andy Baker, 40, from Somerset; Aaron Lacey, 36, from Watford; David Davenport, 38, from Buckinghamshire, and Michael Reynolds, 45, from north London.
The co-defendants told the court they had been invited to the game by Mr Morris's brother and were given a guided tour of the stadium.
Explaining the decision to direct the jury to clear the men, Judge Charles Byers told the jury that in the prosecution's case, Mr Morris had been the "essential core" of the blackmail plot and without him the case could not stand.
David Davenport, who runs a security business, said afterwards: "We always expected we were going to get 'not guilty', it's just a big weight off."
Tracy Stent, a co-ordinator at the QPR First Supporters' Trust, said: "It has been a traumatic time for the club and things have come out during the course of the trial which have been quite extraordinary really, regarding what goes on behind the scenes at a football club in relation to various arguments that were going on.
"From a fan's perspective, we need to just learn from the experience, move on."
Report from the BBC