The camera will assist alignment to within 1/4". If you need completely precise alignment, you will need to make a jig. For most of us using the set focus tool prior to placing our artwork provides satisfactory results. Your photos indicate that you are pretty close to being within the Glowforge specs.
When I use the passthrough and try to print an 18" circle it comes out like an oval. There are also skipped sections and I have to cut it out myself. I understand the 1/4", but the camera isn’t aligned correctly
The most common cause of camera calibration failure is an unstable wifi signal. It is not the strength of the wifi signal, but its stability. Perhaps Glowforge support can help when they get your support ticket.
Those problems are wholly unrelated to the camera alignment. The camera is just an aid for you to place the design on a picture of the material, it’s not used by the machine itself in any way. The circle being oval shaped means the laser arm is crooked or there’s some problem with the movement system – belts, wheels and motors. Here are some guides to troubleshooting that
If the sections that are skipped are where the cut starts and ends, you have just one problem. If it’s elsewhere along the circle, you have a second problem that only Glowforge can help you work through – something related to the power supply and laser tube, or the firmware that drives them.