Employment Law Questions? Ask an Employment Lawyer.
You could advise the ex-employer that you will counter sue for fraud if it decides to file a lawsuit against you. At this time, I would consider the threat to file suit just as a threat and there is nothing you can do to prevent a lawsuit from being filed other than advising the other side of your intention to counter sue and the consequences of the ex-employers actions.
I would simply wait and see what happens to see if in fact the employer file suit. Then consider filing a counter suit.
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