Well, Maikeru Arakawa's Shin'uchi promotional test is almost done. I think he will pass. He clearly already got 3 of the 4 judges giving him a passing grade even if one really didn't want to.
For the patriarch of the school Issho, I think will either give him the pass and say that, "this is the minimum he expects of an Arakawa Shin'uchi." Or fail him but let the majority vote hold up so pass.
He seemed to have multiple reasons why he failed Shinta during the mass expulsion event. He felt it did not met his standards as people were already cheering him on before his performance. He wanted it to be used as an example to show that Arakawa only accept the best and will expel anything else. Finally, its implied that Shinta based his style off of Shiguma's art, the style of the master of both Issho and Shiguma (Shinta/Akane's master who inherited the performer's name) that Issho felt was impossible to copy because he couldn't; so he expelled him.
This led to a backlash against the Arakawa school that was only mitigated because both Issho's personal fame and Shiguma not making a fuss over it publicly as well as playing the mediator with the Rakugo Federation. Tohru is implied to be the only futatsume that actually respected the expulsion instead of just going to another school making it seem the whole incident was to target him, and he was well loved in the Rakugo community. Also those 5 others as well as the ones the left the school after the expulsion have joined other school and likely hold a grudge against Isssho Arakawa. As well as there have been no other futatsume that has even attempted the promotion exam since the incident. Its also all but stated that there is a schism between Issho and Shiguma that could easily lead to the school breaking apart. That hasn't happened yet because Shiguma hasn't done anything, which is implied due to Shinta accepting his expulsion as well as Akane becoming his apprentice, but he will not accept happening to another of his student especially Akane.
I feel while Issho stands by his decision he does have regrets about it, since they have had no one taking the exam since that event; if they can't get new masters eventually their school will die off. His somber attituded once he learned that Akane was Shinta's daughter. He desire to find young talent and him being a judge at that event was him looking for talent. As well as his downcast look during this exam.
Also its more beneficial for him to pass than him to fail or get expelled. As it opens a path of growth for Shiguma's students. Something to drive them on. It would also break a status quo that has hanged over the school.