I have actually repro’ed this by deleting the camera which was on the scene switcher scene and the build still gets the same issue on a full export. The issue doesn’t happen when I roll back to 3.47.2 preview and 3.47.1 preview which I was using previously until I tried updating so something is up with multi scene cameras in that version. Sometimes I can hard refresh the webpage and the first camera to load is correct but I click the next button to the next scene and the cameras all stop orbiting or suddenly change to a camera at 0,0,0 origin. This project works fine in those previous engine versions.
The cameras in the sub scenes are correctly marked as Main Camera I can confirm, this is a long running project I have been working on in Needle for over a year and a bit now that has been fine but I use it to test updates