Earl lost even more leverage with the news that Cincinnati cut George Iloka, who is nowhere near the player Earl is but will come cheaper and won't cost any draft picks, making him a better option for teams that need a safety but don't want to invest heavily in the position. In fact, it's sounding like the Raiders will pursue Iloka, which pretty much kills any chance of an Earl-for-Mack trade (though I doubt there was ever much of a chance of that anyway.)
Honestly, Earl's best move would be to report today in exchange for A) having his fines waived, B) a promise from the team that they will trade him if they get a viable offer, and C) a promise from the team that they will not franchise him in 2019. Then come in, treat the last year of his contract like a one-year "prove it" deal, and do his best to show the league that he's worth every penny he's asking for. And, frankly, I think teams might be more likely to pay him the money he wants if he demonstrates that he is worth it and they don't have to trade a high draft pick for him.