Re: Can I delete these folders?

@cheesegaiyke  Yes, you can delete the Sims 4 folder inside Origin Games.  When you launch the Steam install of Sims 4, the game data used is from the Steam install; the Origin install is completely ignored.

After you've deleted the folder inside Origin Games, restart your computer, clear the EA App's cache:

https://help.ea.com/en/help/faq/clear-cache-to-fix-problems-with-your-games/

and then see if the missing packs will download this time.

By the way, the old Sims 4 folder is probably inside Origin Games because you originally installed the game using Origin.  Installing the EA App doesn't change the location of already-installed games.