My question involves labor and employment law for the state of: Tennessee

I was offered a job 3 weeks ago. I signed the letter and did the drug screening. The background check took 3 weeks.

The background check cleared fine, but the employer rescinded the offer because they couldn't verify my Bachelor Degree (earned 10 years ago in a foreing country with very strict privacy laws).

When I signed the forms for international disclosure I warned them that they wouldn't be able to verify the degree and that I had no way to provide them with proof other than getting on a plane and go fecth a copy of the degree.

They still went thru with the whole process before rescinding the offer causing me to miss out on a couple of good opportunities...

is this legal???

The letter offer says "contingent on satisfactory references, background check and drug screening" all of which cleared with no problems...

Can I sue them for damages? and is it worth it?