If the communication was private, there was no defamation. There are many legitimate Jewish geneological organizations. The DNA aspect of this puzzles me. Among Jews, there is voluntary testing to look for diseases. For example, Jewish women with breast cancer may seek testing to look for specific genetic markers that their daughters may need to know about. Similarly, people of African descent may search for markers as to sickle cell.
But, what you describe is most odd. DNA tests are not all that expensive. The aspect of "a great deal of money" worries me. I suggest that you research this among trusted friends locally and seek referral to someone more expert and more specialized.
We do not have a client/attorney relationship until you make an appointment, we discuss your case face to face, I accept a retainer, and we explictly agree to enter into representation.
It is unlikely that there are sound claims for any of the causes of action (legal bases) that you have listed in your post caption, but there maybe sound claims for fraud, unfair business practices, and other "consumer" claims. You may want to start by doing some serious internet research to see who else has had problems with this outfit. Also, you may want to contact your state's attorney general, consumer fraud division.
I am changing your post categories to attract some responses from attorneys specializing in legal practice areas more relevant to your facts.
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