In Eduyos it says Akavya ben Mehalalel was excommunicated. Here it says it was considered if Akavya ben Mehalalel should be made a zaken mamrei... Where does it discuss / are these stages in a process of treating a bad scholar? Please relate the two.
hg, Spring Valley
The Gemara here does not entertain a possibility that Akavya ben Mehalalel might have been considered a Zaken Mamrei. In fact, it is obvious to the Gemara that he was not a Zaken Mamrei. This is because the Mishnah in Eduyos 5:6 states that they put Akavya in Cherem and he died while he was still in Cherem, so clearly Akavya was not executed. If he would have been considered a Zaken Mamrei he would have been executed.
1) Rav Kahana said here that if the rebellious scholar said what he said because he heard it from his teachers, and they were not ideas that he thought up himself, then he is not considered a Zaken Mamrei. Rashi (DH Akavya) writes that Akavya said, "I heard it from many teachers." The Gemara concludes that we can prove that Rav Kahana is right, because they did not execute Akavya, which shows that he did not have a Din of a Zaken Mamrei, because Akavya cited his teachers.
2) Rebbi Elazar said that there was a different reason for why Akavya was not executed. This was because he did not issue a practical ruling but merely taught what the Halachah is. The Din is that a scholar is considered a Zaken Mamrei and liable to capital punishment only if he actually issued a practical ruling against the majority opinion.
3) From the Mishnah in Eduyos one sees that the problem was a different one. Akavya said that one does not give the freed Shifchah the Sotah water to drink even if she was suspected of being a Sotah. The Chachamim disagreed and said that Shemayah and Avtalyon did make the Shifchah drink. Akavya replied that Shemayah and Avtalyon gave the Shifchah to drink only because they themselves were Gerim just like her. According to the Din, however, we do not give her to drink the water. To compare Shemayah and Avtalyon to the Shifchah was a disgrace, and this was why they put Akavya in Cherem, but nobody in Eduyos ever suggested that Akavya was considered a Zaken Mamrei because of this incident. Rather, his offense was that he made light of the honor of the great scholars of the generation. He was not a Zaken Mamrei because he merely reported what he had heard from his teachers, and in addition he did not rule practically against the Chachamim.
Kol Tuv,
Dovid Bloom