He might of hit a tar snake on a hot day.
Here in SoCal, and other parts of the country, cracked roadways are "fixed" by filling them in with road tar. When the summer heat comes and the road heats up, the tar softens. The change in road surface is noticeable, especially in a curve with the bike leaned over and under power. The rider literally goes from full traction, to a loss of traction, and back to traction in less than a blink of the eye. If the bike is in a curve, it will "hop" sideways to the outside. Most recently in Colorado a tar snake in a curve caused me to hop onto the yellow dividing line.
I don't like to second guess any rider, but I agree with the earlier post. To me it looks like he hit a tar snake, hopped wide, came off the throttle which caused him to up right and go wider, fixated on the fire truck and hit it.
Mark