Oak was required to take music lessons to learn the accordion and piano parts for the show. He didn't show up for them. Then in the rehearsal room he started making requests for changes to be made to the score. He then took an attitude with the director and acted like a diva in rehearsals. Apparently the entire run of the show he complained backstage about the show and made it clear that he didn't like it. So he was problematic backstage to be with now.
Now we get to the controversy. Ingrid Michaelson was leaving on August 13th and had been selling extremely well. They noticed that after the 13th, the sales were weak and they needed to make it into the fall where they had a star lined up to step into the show. They poked around and discovered that Mandy was available for a few weeks to help bridge the gap. They sat down with Oak and explained the situation and promised him a place in the show whenever he wished to returned. They had previously done this with Brittain Ashford and it had shown to be successful. Oak acted professional and understood and gave them his blessing. However, when it was announced publicly he went to his friend Rafael Casal and talked trash about the production. Casal took to Twitter and tried to make a racial situation out of it. The twitter happy Hamilton fans immediately started a controversy without any sort of information whatsoever. They started calling for the closing of the show and destroying it's reputation. It was literally trending on twitter. Oak locked himself in his dressing room, refusing to speak to the producers, cast, or creatives. The cast begged him to openly give Patinkin his blessing, but he refused. He continued with passive aggressive silence. Patinkin had been in rehearsals for a couple of weeks at this point I believe and after receiving hate mail and death threats, he backed away from the situation. The show was left without a star and a ton of bad press. The closing announcement wasn't shocking.
The show closed last month and it was peacefully laid to rest. Little did we know that Oak would revive the controversy in a recent interview where he would claim that the show "didn't cultivate diversity" and continue to push aside his Black leading lady who was Tony nominated for her performance as if she didn't matter. He's made it clear that to him and his friends, WoC don't matter. The interview was nasty and in poor taste and was a slap in the face to his fellow unemployed actors.
He hurt the show and disrespected his castmates. It's rude unprofessional behavior.
Mandy didn't show up for a day of shooting during Criminal Minds and he had a bit of a breakdown during The Wild Party. He may have a spotty history, but at least he never did anything as horrible as Oak.
Also, Oak is a totally mediocre talent who was a minor supporting part in Hamilton, while Patinkin was a Tony, Grammy, and Emmy award winning actor when he had his little controversy. One was a nobody and probably will continue to be remembered as such even if he does end up on a Shondaland show.