Thanks for the screenshots! Our layouts were basically identical. Luckily I figured out the issue (or at least found a workaround)
I found this post from 2023 where a guy seemed to have a very similar problem. For some reason turning the Blendable Location of the material from ‘Scene Color After Tonemapping’ to ‘Scene Color Before DOF’ got it working properly.
I have very VERY little understanding of what blendable location is, so I’m not sure if this will have any unintended effects down the line. Regardless, it’s finally centered and I can die happy… Even though the problem was something completely different, thank you for all the help regardless!