Rapleaf doesn't do social. They are great at demographics. FullContact provides publicly available social profile URLs. Depends on what you are looking for.
4 people isn't exactly statistically significant. FullContact averages a 60% match rate to at least one social profile. Let me know if you find anything better.
It's an API. You could run two separate calls and then merge, or run the excel macro with two separate files and merge. We plan to have multiple queries in the future.