@Realjas If you haven't already, please start with a clean uninstall. Otherwise, the hidden library files corresponding to Pets (or any other packs you once had installed) can get in the way of your launching the game going forward.
https://bluebellflora.com/how-to-do-a-clean-uninstall-and-reinstall-on-a-mac/
Then reinstall the base game only. Next (or start here if you already did a clean uninstall), run the Super Patch (digital download version) to patch the game to 1.67. The launcher doesn't always do a thorough job of patching on its own. I don't know where you found the update you listed, but this post has a link directly to EA servers:
https://bluebellflora.com/sims-3-manual-super-patch-for-mac-1-67/
Launch the patched base game to test. But leave Origin out of it; you can launch directly from the TS3 icon in Applications. (Mojave's security features block Origin in-game, which can crash the game you're playing, but there's no benefit to having Origin open while you play anyway.) If the base game runs, you can install Pets and any other packs you have. Four of them (Ambitions, Late Night, Fast Lane, and Outdoor Living) don't install correctly and need a couple of workarounds. The first is simple: create an alias for any pack that doesn't have one in Applications, alongside the alias for the base game.
https://bluebellflora.com/sims-3-packs-not-showing-as-installed/
The second workaround is to copy files from those four packs into the folder for your newest pack by the date EA released it. This video shows you exactly what to do:
If you're not installing any of the four problem packs, you can skip both of those workarounds. But if anything goes wrong, please post back with a list of the packs you're trying to install, as well as any error messages you see.
Thanks for the instructions, but alas after a complete uninstall, reinstall and updating it still fails to launch. I even ran some system maintenance routines and rebooted and again no results. :/
Just for the sake of specificity, I only installed and updated the base game. I didn't bother with the EP.
@Realjas When you try to launch the game, is Origin running? If so, close it, restart your computer (keep Origin closed), and launch TS3 through the icon in Applications.
If that doesn't help, or if you've already taken Origin out of the picture, you may need to edit the game's .sgr files. Luckily, someone has already written out instructions for your card. Please read them carefully and then make the appropriate edits to both graphicscards.sgr and graphicsrules.sgr.
https://bluebellflora.com/2018/07/24/sims-3-mac-players-i-need-your-help/#Filesready
And if this does work, please let us know. Bluebellflora still needs confirmation that the edits for your card are effective. If you still can't launch the game, please tell us as well; any feedback is always appreciated.
Once again, I would like to thank you for taking the time to help, BUT...
It didn't work. I went back and made sure I followed the steps precisely, too.
I looked to see if it perchance created the DeviceConfig.log before crashing and no. There is no log or The Sims 3 folder in my Documents/Electronic Arts.
@Realjas You don't have to post on that page; I'll pass this thread on to Bluebellflora. (Maybe she'll have another idea for you as well.) In the meantime, there's one more thing you can try. Do another clean uninstall, create a new admin user account on your mac, and install into that account. Then patch the game, and if it doesn't run, apply the .sgr edits again.
A couple more questions: what OS were you running before Mojave? And do you have any antivirus software, or perhaps a program like Mackeeper that's supposed to clean or organize your files for you? These are notorious for messing with your system, and most of them aren't safe to run on macs at all.
