That's a very specific number. Interestingly, Diamond admits that indeed Alienware abandoned them after the high failure rate seen in the cards. You'd think that would be unlikely if there was only a total of 188 cards that were defective. Diamond is blaming an Engineer on their payroll as the reason for the false information, claiming he leaked information to Alienware that led to them leaving.
Can they be trusted? If there was indeed a manufacturing defect, 188 is an awful small number to have even been discovered – cards from other manufacturers probably have higher failure rates than that.