You are reading a tafsir for the group of verses 12:80 to 12:82

Among Joseph’s stepbrothers there was perhaps one brother who was different from the others. He was the same brother who had advised in the initial stage that Joseph should not be killed but pushed into a dry well, so that any caravan passing by could take him with it. That brother faced the same situation in Egypt and he separated himself from the others. His sense of honour prevented him from facing his father before whom he had already been proven guilty of losing a brother. He did not want him to think him guilty of losing yet another brother.