Board Thread:News and Announcements/@comment-3309116-20131012164814/@comment-1447397-20131015065943

Found it. He said its already set in stone that Rohan wont appear in part 8 but ironically another manga artist will appear

http://imgur.com/TOVoNTT,5Tik1mD,8G5U3R8,SdZtwK1,07oOAHU#0

As for the family being rich he might of forgotten, Araki has said countless times that he forgets a lot about Jojo and that the fans know more about it then he does.