Of course you can send a letter in your own name, being truthful (and very careful), but this could get very complicated, fast. You need to consult an attorney.
This answer is intended to be taken as general information and not as specific legal advice. You should always consult a qualified attorney and make him familiar with all the relevant facts in order to get proper legal advice. Every case is different, and they must be evaluated on a case-by-case basis. David N. Smith 812 W. 11th Street, Suite 201 Austin TX 78701 (512) 457-0100 defenseattorneysmith.com
You should consult an Austin litigator who knows something about defamation and tortious interference. I would expect that an attorney could meet with you , get the facts and send out an appropriate cease and desist letter for $500-1000.
Of course, you also need to be prepared to decide what you will do if the letter doesn't work. The statute of limitations for defamation is one year, so you can't sit on the situation too long, if you need to file a suit. You do need to consult an attorney very soon.
This answer does not constitute legal advice or create an attorney-client relationship.
A local lawyer wouldn't charge much for a cease and desist letter, but it is unlikely to be effective after you cried wolf. A tortious interference with business relations claim can be investigated.
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