I think this is the first description I have heard of the Rogue One Vader suit. They guys at Making Star Wars have seen a picture and describe it in this podcast:
http://makingstarwars.net/2016/05/episode-128-makingstarwars-nets-now-this-is-podcasting/
http://makingstarwars.net/2016/05/episode-128-makingstarwars-nets-now-this-is-podcasting/