Edwards, who is now honorary life president at United, believes the club could be thrown into financial chaos if the Glazer family decides to leave the club.
United remain almost £700million in debt, following the Americans take-over of the club.
“It concerns me that the club are so much in debt,” Edwards said.
“The club are not in control, the family are in control of the debt. I can understand where the fans are coming from with their concerns.
“I’m not going to make any accusations because, up to now, they have behaved fairly well, supporting the manager. And they haven’t disrupted the running of the club or the personnel within the club.
“But time will tell. The crunch time will come when they exit. Will they saddle the club with debt or just sell the club for a profit because that’s all they are interested in? How will they leave the club?”