Troubleshoot section fill

I am trying to merge two different models and now my section cut fills are not accurate. Normally, I would turn off the section cuts and then turn levels of the model on and off to check walls and fix non solids. In this case, I am merging with an existing model that is not set up to turn off layers like roof, second floor, etc. I can’t just work in Xray mode because the model is ridiculously complicated and hard to view in X-ray. The problems seem to be at doors. How can I fill the section cut fill?

I fixed it, but it was painful and tedious.