Wanted to add to this and say I ran into the exact same problem when testing projects on the Quest and could not figure it out.
The only ‘solution’ I had was to manually show / hide objects in the scene based on what the user could see from their location. For example, we had pre-defined teleport spots and I would have a list of ‘viewable’ assets associated with each spot. When the user teleported to that spot we would show everything in that list, but hide everything else from being rendered. However, for ‘free roam’ teleportation this most likely would not work.
I have a feeling there is some actual setting to fix this but I went through all the same project settings you listed and tried different combinations but no matter what object culling would not happen properly on the Quest.
If you ever find a solution to this problem I would love to know it as well!