Welp, I was wrong and I’m man enough to admit it. I guess they were holding that Vader pod for another promotion. I gotta say though, when I talked to Shop@Home, they seemed pretty definitive about it “never coming out.” Did they really not know? But thanks to this comment by Zrath, I hotfooted it over to Shop@Home’s website to check the in-store calendar, and by jove he’s right! It IS coming out. You can get your mitts on one by spending $60 or more on LEGO Star Wars sets from April 13th through May 3rd or while supplies last, leading right up to the annual May the 4th be with you spend-ravaganza. This matches the original promotion restrictions way back in December of 2017.
With May the 4th on the horizon, and Solo coming out later that month, I’m guessing that was the reason for the delay. I still don’t buy the QA issue. But maybe that’s because sometimes buying into a conspiracy is easier than the truth. /shrug