Solon Credit Union writes Fraudulent Cashier Checks

I was given 3 fraudulent cashier checks by Andrea. She said "Of course they are good." So I cashed them for someone on January 18, 19, 21 on February 5 much to my surprise they were returned as fraudulent. I filed a police report and I am taking the Solon credit union to court for Gross Negligence and not practicing due diligence. My court date is in April. How can these fools let someone withdraw their money before the check clears? I wouldn't bank here.