I just recently bought a 10 $ energy pack because I have always wanted one of those regalia sets and while I did get one piece of the set that I wanted, to my dismay I did not get the other is that a bug? Or are you just supposed to receive one part of the set. In my case I got a Chapeau of the Gold rose but no tabard.
Correct, when you buy the promo pack you get ONE piece of Rose Regalia gear.
You'll have to buy another pack and hope you get lucky, or trade with another player to get the second piece.