Initially I called a Samsung recommended appliance repair outfit to fix the latch. The technician informed me that he does not fix latches. I need to buy a full new door for the microwave for $215 plus he charges $165 to come to my house. I got angry and did some research and it turned out that this is a very common problem. I ordered part PS4229162 "door key" $6.67 then followed the instructions on a youtube video by zimsjeep "Repair a Broken Microwave Door Latch" to install. At first I struggled a bit hooking up the spring to the frame, but then I used a slim plier to hold the spring (instead of my fingers) and that did the trick.
I r/r the bulb cover, I then removed the burned out bulbs w/ a rag in case they broke they wouldn't have cut my fingers. You turn the bulbs lefty loosy. Installation is just the reverse. Install each bulb and turn righty titey, just snug the bulbs into place. Replace Glass cover and insert one phillips screw in plate and re-tighten
Removed control panel, discharged HV capacitor. Removed old diode, tested to confirm failure. Replaced part. Other than the removal of the panel swapping the part was almost as easy as replacing a light bulb.