Call Boston Childrens Hospital, they might take him pro-bono or direct you to someone who can help, and also check out the International Childrens Heart Foundation
The Penn State Hershey Childrens Hospital Program goes to Guayaquil, Ecuador every year
there is also a Transposition of the Great Arteries group on Facebook...even after surgery your cousin will need follow up care for the rest of his life. I wish you all the best.
Hello and welcome to our site! You may also try contacting Texas Children's Hospital as well. They are located in Houston, Texas. I know that Dr. John Brownlee works in other countrieds to help children get treated here in the USA. He is in San Antonio Texas.