Any more details you can give would be appreciated. Ideally a league file where I can see this problem, and a description of what you did to make it do this. Cause I doubt the playoffs are broken in general, probably it's something specific to this league.

I simulated the regular season, then edited the playoff teams to match the actual NBA playoffs. The LAL made the playoffs on their own, while the LAC didn't even make the playoffs. I'm assuming the taking out LAL and putting in the LAC confused the game. I remember early on when the LAL were added, the game would get the two confused. Is there something in the code that refers to both teams as just LA?

It'd be a bug if that was true. I'm not aware of any problem like that. If you could send me a league file exhibiting the problem, where I can sim the playoffs and observe it doing the wrong thing, that would make it easier for me to figure out what's going on.