Good news, the fuses have arrived, I mounted it and luckily there is no other damage, it worked perfectly the first time I started it, I left it on for about forty minutes and it didn't give any problems. In the end, the main culprit was the failed STR. What I still don't understand why the CPU paste makes electrical contact between the heatsink and the STR, I have now put a piece of thermal pad in place of the paste.
Thanks again for the fundamental help.
https://youtu.be/QjD3pxM3GrI