With all due respect to all, I have a slight case of dyslexia, am completely tone deaf (ask my wife) yet was able to learn Spanish at the ripe age of 34. Sure it has taken more than 10 years to be relatively fluent but what's the rush? I do have a Dominican wife and kids but to my credit I like to study Spanish. In fact is one of my main hobbies.
What I have learned is for adults there is nothing like learning to read and write first. Regarding immersion without intensive grammar studies, I have as of yet met a foreigner who used this method that any native Spanish speaker, much less a Dominican, would think is fluent.
Spanish is in fact a very easy language to learn once you learn the verbs and some nouns and to this end google translate is your friend. After a few months of intensive grammar lessons, every day, I would start trying to read the news in Spanish. Forget Dominican newspapers as they are overboard on the fancy Spanish. Go with the Miami Herald or Univision or say a news source from Catalonia, as it is less complicated than ones from Madrid.
Furthermore, there are two real reasons I've seen people don't "get" Spanish; unwillingness to study and make a fool of themselves at times.
Finally, there is no such thing as a Dominican language, it is Spanish with regional idiosyncrasies, no matter how many "experts" say otherwise. I recommend learning correct Spanish and don't imitate the locals and before long you can expect them to use their best Spanish with you.