I figured what was wrong on my end. I play on PC. If my Xbox gamepass account is linked to my EA app, it will recognize the game as running the gamepass version of the game and not the game and dlc that you purchased, and DLCs will not work when offline. If you unlink your Xbox account from the EA app, and restart app, then it recognizes my game again as Sims 4 deluxe edition and will play my game and all DLCs even when offline. They force that app down our throats and the damn thing still isn't working right. Get your crap together EA. 😡
EDIT: I have a feeling that if you are subscribed to any of the EA plans that includes Sims4, that problem applies to you also.
EDIT2: What I described above worked yesterday, but today I can't play offline anymore (misunderstanding with IP provider got our internet cut off for the weekend) I have to launch the game using my phone hotspot. This is very frustrating and demonstrates the woe of not owning any type of digital media in this age. If this is not intended EA needs to fix it, this issue from browsing the forums seem to exist at least since the start of the EA app.