Board Thread:Questions and Answers/@comment-99.172.21.164-20160601180128/@comment-22498334-20160609003120

And yes, they do. Hide more or less helps Amon, Akira, Shinohara and Juuzou with their respective ghoul investigations whlch leads to him revealing that Kaneki Ken, is his best friend. Its in TK manga chapter 89 through 90, if you want to verify it.