I can see it there. Haven't downloaded it though, since we haven't moved forward to 2013 yet...
Try this link, then. It should bring you to the download screen for it.
I hate to ask the obvious but is your company on Autodesk's subscription plan? I do not see you logged into the page and unless you are, you will not be able to download a feature that is only available to subscription customers. If your company is on subscription, find out who is in charge of the master account and have them add you as a user.
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