What are the challenges in applying for a second Non-Immigrant O visa for volunteering from Laos, Cambodia, or Vietnam?

The inquiry discusses the challenges faced when applying for a second Non-Immigrant O visa for volunteering from neighboring countries. It highlights a specific case of rejection due to the lack of a work permit and questions whether this requirement has changed over time, as others have reportedly not faced the same issue. One comment mentions that Thai consulates in Laos require proof of work permit application for this visa type, suggesting that rules may vary or have been enforced differently.