April 2021
So I have the base game and couple of expansion packs in physical form, I cannot redeem the codes online, as I already did on one of my old accounts, to which I don't have access anymore. I was thinking of buying some extra expansion packs on origin, but I am not sure if the base game would be read if not added into origin to play with the digital expansion pack. Did anyone done it that way? Does it work? I tried to reach to EA help before about not being able to add these onto my origin, but noone replied. I'm not going to re-buy these again, they were expensive.
April 2021
@OwlTheDestructor This might work, or it might not; there's no way to know until you try. Some players even report that it does work for a while and then stops after an Origin patch.
The easier path is probably to try to recover your old account: if you have enough information about it, a support rep may be able to restore it for you, and perhaps transfer the packs to your new account if that's what you want. If you can't get through to support, try choosing a slightly different category of issue or changing the location showing in your browser window to U.S. or U.K.
You could also wait for a sale of Sims 3 content. Expansions were $10 U.S. last month, which isn't bad at all. And the "Starter Pack" is always $20; it includes the base game, Late Night, and High-End Loft Stuff.