Well not to be rude or anything, but MG had the right to shut down the Higurashi fantranslation, despite that the Sisters also had an email from the original creator encouraging and permitting the translation.
Especially that
-unlike the ~3 year old email from Navel GP has (it'd be nice to see it screenshoted down by the way)-, Ryukishi's email was sent in
April 2009.
So what exactly is different in Shuffle's case?