Actually, the Church portfolio that the bishops managed held stock in a mainstream publishing company that happened to have a branch which published porn. Please present your evidence that the bishops "knew" all the activities of a company they invested Church funds in.
Why not check out LifeSiteNews.com, Nov/2/2011, article,
“German bishops’ company: It’s not porn, just erotica, so we’re suing the ‘slanderers’”