Yeah the suits they wore were specially made to resist the stings which can defeat the usual bee outfits quite easily, they have a quarter inch long stinger and can sting multiple times.
One thing I don't get and have not seen any mention of it, is why they nested in a tree 8' off the ground? Apparently they are usually a ground nesting bug, using holes often left by small critters and rodents etc., at least in Asia.
I thought maybe climate but I don't think there is much difference between the climate in western WA and the Pacific coastal regions of Asia, both are fairly moderate, often wet climates.