If the focus is on reggaeton, the focus is not limited to one zone or country. Reggaetón is the dominant and predominant pop music form all over Latin America, from Chile to Mexico. While Caribbean in origin (it has Jamaican heritage that was refined in Panamá and Puerto Rico), so playing that music will appeal to people of all heritages. And there are a few bachata and salsa songs that fit this kind of format, but not many.
But if they focus more on salsa and bachata, they will loose nearly everyone except those from the Greater Antilles.
The website -- English only, curiously -- describes the format thus. (I won't bother with a bunch of "sic"s. Just know that the wording is exactly as presented, errors in spelling, punctuation, tense and style included):
Rumba 92.5FM and 880AM is the only and unique tropical music station in the Houston Market.
We play Salsa, Merengue, Vallenato, Cumbia, Bachata, Urbano and Reggaeton Hits.
Core Artist Include: Marc Anthony, Gilberto Santa Rosa, Grupo Niche, Celia Cruz, Aniceto Molina, Joe Arroyo, Victor Manuel, Olga Tañon, Romeo Santos , Hermanos Rosario, El Torito, J Balwin and many more.
So, is there much of a Caribbean Spanish-dominant population in Houston? I'd expect this format to be dead on arrival in El Paso or Brownsville, but could Houston be more diverse than those border cities?