First, I tried if it worked without these two pins, but it just would not post. I tried inserting two pins from an old AMD CPU into the MB socket so it made contact with the CPU, but it woulnd't post neither.
It took me a while to get all the necessary items to fix it: soldering station (with flux, tin, etc.), 0,3mm copper wire, an AM4 socket motherboard to test it...
I followed the same steps than this video:
Here are two pictures of the fixed pins: