I think what you've heard about the exporting of the DR cigars is correct. I was also warned about fakes. I saw some vendors selling cigars and IMO, the prices were too good to be true, so I passed.
I did visit a small factory in Punta Cana (Domenico Cigars). The tour was good and the prices reasonable. I was able to try a cigar and then was able to buy different cigars (different sizes, wrappers, etc.) I was under the impression that they were opening a showroom in P.P. but I don't see any information on their website about this.
Enjoy your trip!!!