You are absolutely correct. I finally found the other 5 screws. I felt behind the panel and could feel a screw sticking out of the top board. With a flashlight and driver, I poked around the hole that held the screw with the button and found another screw. There were 5 of them. I did not understand that the button screws were used to cover the real screws. The panel is out and I can get to replacing the rest of the lights.
One last question. The factory thought to seal the heck out of the wires that came from the lights. Do you recommend putting some caulk from the inside to seal the wires or do you rely on the rubber gasket of the lights?
My replacement LED lights included fresh rubber seals. I replaced the seals, and lubricated with silicone grease, but I did not use any additional chalk or sealant. I don't think it would hurt to use chalk or sealant, but can't say if it is necessary.