This issue has still not been resolved. Support has responded with basically the same thing you posted @misterski, they then have not responded after I have tried their fix, and have not gotten anything back yet. It has been several days now.
Topic pretty much says it all.
Go to cart, check the box, made sure payment info was good, pressed ok, and it sent me to the home screen with the expansion both not available, and not showing up in my account history.