@jarzzie Yeah, Steam DLC doesn't work on Origin, that's how it is. If you have Steam DLC, you need to run the Steam Version.
At this point, I think the best you can do is the following
1. Backup your user files found in Documents\Electronic Arts\The Sims 4
2. Uninstall both Origin and Steam version with all DLC (so that there's nothing Sims 4 left on your computer)
3. Reinstall the Steam Version with all it's content, then start it on Steam.
4. Your Origin DLC will be missing, so after starting the game, close it down and start Origin (Steam still running).
5. Go to the tile of the Steam Game on Origin (if you have that, otherwise just use the Sims 4 one on Origin) and start installing the DLC you have on Origin.
6. After that is done, start the game through Steam.
7. If you now have your packs, move the backups of your user folder back in case your saves don't show up anymore.
For me, the packs I installed (one Content from Steam, 3 from Origin) showed up in my game.
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