There is no way for the caller to track a post here back to the call recipient. Given the unknown phone number of the recipient, the unknown delay between the call and the post and the hundreds of calls made every minute by the robo-dialers, it would be vastly more difficult than finding a needle in a haystack.
While it is certainly good to think about what you are revealing in your post, I think they would have a hard time making a case without more vectors, and this particular scammers is not one who can afford to take anyone to court. I'm sure they are far more interested in AVOIDING the legal system at all costs.