You're not warning others, you're acting in bad faith because you can't accept the reality that you damaged your own product, and instead now try to shift it to be the company's responsibility.

You say NK is blaming you unjustified - but let's be real here for a second: You didn't check the PCB before building, and the pictures clearly show damage to the PCB from inserting switches wrongly. How can you be so certain that it wasn't your fault? Why are you so quick to put the finger on NK? As others have said, it's extremely rare that a PCB leaves a facility faulty, it's even rarer that the socket in question happens to have damage marks that correspond to wrong switch insertion. So what do you think is more likely: That somehow a reputable company like NK tries to sell a reused PCB that was damaged and not checked by them before reselling, and that happened to go to that one person who also doesn't check his PCB before building, or that you just fucked up and damaged the PCB yourself? Ima go with the second option 100 out of 100 times. So stop crying and victimizing yourself like you got screwed over; you didn't, and I feel genuinely sorry for NK for having to deal with people like you.

You are the reason why I despise working with customers directly in any type or form. And judging by how the community is reacting when it is not shying away of calling out bad companies you should reevaluate your stance, accept the fact that you fucked up and learn 1) to check PCBs before building and 2) how to insert switches correctly.