another alternative is to turn player on clubs. Those players didn't sign contracts to play in this competition, it could be argued that they are not contractually bound to play in it. Inform the players as soon as they turn out in that sham of a competition then they will be banned from playing for their country. But offer legal support, with contract lawyers, to assist them with exiting their contracts.
In this way you are making the players hate the clubs for putting them into a competition without consultation, without any forewarning and against their ethics. It will turn players against these CEOs and owners, which it sounds like might already be the case.