This is making the assumption Cuban medicine really is as good as it’s touted to be. If it’s not true, how did the Castro regime make Cuban doctors appear to be so competent?
I wrote this answer on the very connected topic of Cuban medical diplomacy with one focus on Angola, and one on the influence of the regime's literacy campaigns on education. One additional point for your question: medical diplomacy was/is very cost effective for Cuba in that training doctors and carrying out those specific operations are comparatively not that expensive, but bring many diplomatic/economic advantages as I discuss there. I've included sources to show that these are not just rumours.
Hope this helps!