More on the legal (and practical) issues around a presidential candidate’s withdrawal (DEREK MULLER, 6/28/24, Election Law Blog)
First, Rick is right that the DNC rules for “pledged” candidates really just a pledge and not binding. Per IX.E.3.d, “All delegates to the National Convention pledged to a presidential candidate shall in all good conscience reflect the sentiments of those who elected them.” Likewise, IX.C.7.e, “Eligible delegates may vote for the candidate of their choice whether or not the name of such candidate was placed in nomination.”
…just allow a conscience vote.