If I were the Bills FO I would seek to add new language to the contract, and perhaps go "all-in" by upping the ante. For example I'd add language that says any time missed for substance abuse you would lose all bonuses going forward. Have Dareus sign a modified contract. In addition to that I'd actually offer additional benefits based on playing time, performance, and perhaps even a playoff bonus. Significant money to inspire him to perform and take leadership. If for whatever reason Dareus decided against agreeing to the deal, I would actively shop him before the draft.