Tothe3nd As a side note, a dxdiag is a system report, not a live debugging tool, so it doesn't matter when you run it as long as you run it after the first signs of trouble. (The Windows Error Reports at the end are often informative, so it's helpful for those to include any errors related to the problem at hand.)
The WERs in both of these dxdiags are purely crashes of the Desktop Window Manager, which could explain the Sims 4 crashes. The next troubleshooting step for this kind of problem is a clean uninstall and reinstall of the graphics driver, as described here:
https://crinrict.com/blog/2019/02/clean-re-install-of-graphics-drivers-with-display-driver-uninstaller-ddu.html
If this doesn't help, could you test the GPU in a different computer? Given how low the power draw of an RTX 3050 is, you could probably install it into almost any system, certainly any that has at least one available 8-pin supplementary power connector. This would be the easiest way to test the card itself, assuming the system it's in is otherwise in working order. If that system currently has an AMD or Intel card, you'd need to DDU the driver, as above, before installing the Nvidia driver, and DDU again to go back to the original driver. But if the system already has an Nvidia GPU, there's no need to touch the driver.