Bought Cubase 4 -> 8.5 Pro upgrade. Can't activate.

I bought the $299 8.5 Pro upgrade thinking that all I would need was the eLC license code from my Cubase 4 AI version. When that approach did not work, I saw that there is a known upgrade problem with a published work around -
Trouble is, I long ago deleted my original install of Cubase 4 AI so I have nothing to upgrade on my HD. I don t have a DVD because I downloaded the install from the Cubase site. Is there any way I can either re-download the original v4 AI package, upgrade it and then upgrade again to 8.5? Is there a shortcut you could provide? I need to get this working as soon as possible for a project. Thank you for your help!

UPDATE - the problem was I bought the update for Cubase 4, not Cubase 4AI. There is another option farther down the list of the potential upgrades that just says “Upgrade from Cubase Elements, LE, AI, Essential, Studio, SX, SL or Sequel” and I just missed the “AI” stuck in there. I got a refund on my initial purchase, bought the correct version and now all is well.