KMC gave a total BS reply to the OP's inquiry. There is no way that the OP's method of cleaning his chain had anything to do with the multiple plate fractures. KMC did not address the issue at all. I'm hoping they reply with a meaninful analysis of this failure. I hope that Papa Ado sees this and contributes to this.

FWIW, I will personally avoid KMC chains at least until someone replies with a satisfactory response, not nonsense.