Joeharkay When you tried to run sfc, it looks like you pasted the command twice, so it didn't actually run. The three outcomes are "did not find any integrity violations," "found corrupt files and successfully repaied them," and "found corrupt files and was unable to repair some of them." Only the last is an actual problem, so let me know if you get that. If you're not sure whether DISM ran to completion (you'd see an 100% when it finished), please run it again as well.
If you still can't play, please create a new admin Windows account. Make it local, as in, don't link it with your Microsoft account. You can choose "I don't have this person's information" and "continue without an email address" or similar; point is, do not supply an email. You'll be able to launch Sims 4 without reinstalling anything, but your user data won't be available. Let me know how it goes.