That's a bunch of double talk. Being at will has nothing to do with insurance. If you were given insurance as a benefit and hurt your knee, then you were covered for the period you were covered for. Letting you go would mean you dont' get future insurance, it would not mean you didn't have insurance when you did. Someone can be sued. Depends on how the insurance was set up and the laws in your state. But no attorney said sorry, there is no one to sue.
Actually, I sue my employer... they fire me. They ended up firing me anyway, but still, not worth suing over at the end of the day. My out of pocket ended up being about $20,000. A lawyer would have cost me a lot more than that
If they were charging you hourly instead of charging contingency then again you're proving the lawyer told you that you had no case, the crap policy you bought didn't cover more than they paid. If you had a case, they'd have piled on pain and suffering and you would have made more than $20K after paying them.
You really are a bad liar. You don't realize when you're talking to someone who knows more than you about what you're talking about