I have a photo of a Dominican Republic aircraft wearing the black/yellow SAR markings. It’s in one of my Latin American aviation books by Dan Hagedorn. Will scan it and post it.
PEB, I have never seen any evidence of that roundel. I think it’s a misinterpretation of photographic evidence. From afar, it can appear that the star in the center of the small roundel with the same colors is only a yellow disc.