Hi Yunus,
What's the reason for setting this up via user roles? The User can toggle this on and off as they please, right? So security isn't an issue. If that's the case, then why not use conditional visibility on the contact page. Add the boolean on the account entity, which users can edit. Then when navigating to the contact page with a (nonpersistable) helper object you can check this boolean and show certain details. If you like, I could make a quick demo of this.
https://docs.mendix.com/refguide/common-widget-properties/#visibility-properties