op-ed does not make it fact
Recusal in a situation like this is always a question of judgement. The general rule is that a person who has an interest in the outcome, should not be allowed to pick their own judge, and (in the case of a judge) should not be allowed to decide the case. One who has an interest may or may not be impartial, but in the interest of preserving public trust in "the system," (as well as giving the parties an unbiased shake) that person should step aside from this one decision.
Much as I detest the ABA, it has a point here. Cruz is potentially THE party in the case!