It appears to me that Jim's been told the (read: a ) story by the dear Krameks without even having read the letter. The story must have been: I have informed the employer about the hack - which is only a part of the letter

I suppose it's possible.

Jim's 'understanding' was that Naomi was fired about 3 months after Andy's letter, so therefore (Jim's words) the letter wasn't necessarily the feather that broke the proverbial camel's back...

According to Naomi, she was fired about month and a half after the date of the original letter....and just a few days shy of a month after the alleged email from Marcia.