I'm not the OP but I experienced the same. I have been contacting developer support through Contact Us > App Review > Other App Review questions. I have already sent multiple messages in the hope of getting more information about my rejection, but the Support team keep asking me to reply in the App Review Reply Section - even though it was mentioned that App Review team will not review replies. I also followed the advice and replied there (not expecting a reply), no update for more than 9 days.

I received a reply regarding my appeal today (more than one week after i sent the appeal). It was rejected and there was still no attachments and any additional information about what specifically about my app was lacking quality - they just cited the initial rejection message and App Review Guidelines.