Regarding Red Light in SD, Google used to be friendly with sex tourism content, but they've made this info increasingly hard to find. Also, what is discoverable tends to be very dated. I almost went to Medellín instead of DR. Can you imagine if I relied on content from 1 year ago? I'd be very disappointed showing up and finding out that much of the activity has been shut down, at least from what I understand. I'd rather hear from real people who have had recent boots on the ground.
Regarding other things to do, I don't see fault in asking real (likely like-minded) people instead of relying exclusively on a search engine. It's good to gather opinions.