Remember to also evaluate where your source came from. "Whythiseventwasntagnocide.org" is not a great place to get your primary source, even though it's unlikely they doctored the document. Talk to Dr. Clark or Jamie if you're unsure.
You may also be able to search WISE for narratives of those involved in the event.
Google smarter! add site:.edu to the end of your search to only return results from college or university websites. Those are some of the best places to look for primary sources.
You're hopefully not just finding a primary source just because- you should think critically about what it can tell you about the event that an academic source might not be able to. Just like any source, primary sources aren't usually pure and objective.