Windeguy is right - having a US connection will hurt more than help, because they look at it as more reason the Dominican will stay in US illegally.
Many years ago [early-mid 80s] we took my retired father-in-law to the US Embassy to apply for a visa to visit us in NJ. Me, my husband and our 2 children [then little kids under 5] went with him, thinking it would help. I went up to the window when it was his turn, and spoke to the guy there. He was very nice, and very informative - he came right out and told me that his having a son in the US didn't help, it hurt. I guess he saw the surprise on my face, because he softened a bit, and asked more questions. He nodded several times when he heard there was a wife and 5 other children in DR - and long story short, he got the visa.