Id have Kato do it (join in on the chunin exams) but Gero's jounin said no go (which is understandable due to how messed up Kato is right now).
Additionally there is no point in having team Shinichi do it since all his students are basically chunin now.
-----------
EDIT: I also saw that Kato has been changed to a different team. Just wanted to say thank you Gero. Also is there a way to transition between teams that you had in mind? (Question targeted towards Gero)