The best strategy to synthesize information from sources regarding boundary issues would be:
Find unbiased sources and find out if information was left out concerning the people, land, or resources in the boundary region.
This approach emphasizes the importance of obtaining a balanced view and understanding multiple perspectives, which is crucial in boundary disputes where interests and narratives can vary significantly. By seeking unbiased sources, you can ensure a more comprehensive understanding of the complex factors at play, rather than relying solely on potentially biased or limited perspectives from governments or single authoritative sources.