Of course things are not always what they seem. The flash point of oils is where the oil evaporates just enough, so a flame can be generated as a flash. It is not sustained.
Most two stroke oils that must mix with the gasoline, have been pre-mixed with lighter substances to facilitate the gas mix. This lighter pre-mix has low flash values, and it serves as fuel once it passes the carb jets.
To know what is what, you can conduct a heat test. A typical cylinder wall temperature is about 200°C That happens to be a household iron at highest temperature. I did a few tests some time ago with different oils. The good oils had no problem with 20 minutes at 200 degrees.
Elf had become tarlike thick, and castor had lost all lubrication, and had dried out.
Mobil and Putoline were spread out, but still normally thin in viscosity.
Edit.
Standard test amount was one single drop inside the small cup dremeled in the iron sole.