Brought the Alchemy lab from Proventus in Whiterun, along with everything else. I noticed, having exited the menu once to check gold and then buying everything else, that the alchemy lab was still listed.
Went into the house and, sure enough, the lab wasn't there. I checked the UESP and apparently Dawnguard has caused that to start to become an issue.

Being on Xbox, I can't just uninstall Dawnguard like PC users can. Is there ANY fix for this, or am I stuck waiting until they release an official patch for this, if ever? =/