It's entirely reasonable to ask for clear, easily verifiable proof. As Ronald Reagan famously said, "Trust, but verify." If he is indeed serving in Ukraine, I have genuine sympathy for his courage , however misdirected it might be—and would welcome his firsthand insights from the battlefield. If not, then, as any current or former servicemember will tell you, stolen valour is taken very seriously. Apparently, there are a significant number of so-called "Walts" (military impostors), and quite a few seem to be in Thailand for reasons unknown.