If a user suggested an edit which was later rejected, they should still be manually pingable on the post.
Comments should be used to request clarification and add details to improve the post. The system should be the one to help educate users about rejected suggested edits, not other users in the comments. It's distracting and doesn't help improve the original post.
So unless you have another usecase where a rejected editor would need to be pinged, I vote nay.