Bill McMurdo also criticised the way the Pittodrie side have conducted their business with suitors Watford, who had a £2 million offer rejected for the 21-year-old.
Aberdeen called the bid “insulting” and rejected a transfer request from Ferguson, saying they saw the player as part of their long-term future.
McMurdo insists they’re going back on their word having told Ferguson when he signed an extension in 2019 that they wouldn’t stand in his way if an English Premier League club came calling.
He told the Daily Mail: "The player submitted a written transfer request because he had no other option.
"He has had a great time at Aberdeen. He has been first-class for them and they have been first-class for him. But now they are obstructing his progress. And I think they have let the player down.
"They told us when he signed the contract initially that if a Premier League club came in, they would not stand in his way. Lewis was absolutely up front with them and told them his ambition was to play in the English Premier League. They said: 'Trust us, we won't stand in his way'.
"They said they would consider it a good thing if he went to play in the English Premier League. And when we signed the extension to the contract, they reiterated that stance again.
"In the last couple of weeks, a club asked if he was available and when they intimated he could be, they asked: 'How much do you want for him'. Aberdeen have since refused to give them a price and I can't understand that.
"I have said to them that I've been in this business a long time and I have never known a buying club to ask a selling club for a price only for the selling club to say: 'No, make us an offer'.
"They have never said if they want £4m or £10m. And how can you conduct business on that basis? That's a mockery and I am upset because this is an opportunity for Lewis to realise his ambition. And I think the club are going back on their word and the gentleman's agreement we had.
"I think they are holding out for a massive amount for him and I don't think it's going to happen."
Meanwhile, Rangers are reportedly preparing a multi-million pound bid for Ferguson as they look to make him the third member of the family to star at Ibrox after dad Derek and uncle Barry.
The Ibrox side have long been linked with a move for the Scotland under-21 international and Football Insider claim they are ready to swoop this summer as they look to take advantage of the disconnect between player and clubs.
Ferguson has made 124 appearance since moving to the north east from Hamilton Accies in 2018.