Hi MrsTragicClown,
Welcome to the forum!! Thank you for noting what you've already tried. It appears that this is a bug that has been going on since Sims 4 was released. I tried searching on the problem. But only came up with the tips you've already tried.
However, an idea popped in my head. Have you tried a factory reset, to see if that helps?
Move your Sims 4 folder to the desktop or some where safe, and rename it something like Sims 4 Current. Go into Origin, right click on Sims 4 and select Repair game. Once finished launch the game to create a new Sims 4 folder.
Go to Documents > Electronic Arts to confirm you've got a new Sims 4 folder.
From here, you can copy your files and folders over.
Options.ini File -- Video and Game Options
Saves Folder -- Game File Saves
Screenshots Folder -- Photos taken in-game
Tray Folder -- Sims, Houses, and Rooms
Mods Folder -- Mods and Custom Content
Read more about a Factory Reset in the link below:
http://sims4.crinrict.com/en/2014/09/resetting-the-game-to-factory-settings-without-reinstalling/Hope this helps,
MrsFlynn