Plastic, I didn't say real-life with you present at the scene but that you had seen genuine explosions as I think many people will be influenced by the Hollywood version where Harrison Ford can out run the fire front.
I was of course questioning your experience.
I just looked at that explosion again and would not like to assert that it was fake. Fireball development was uniform, rapid, and circular as you would expect where there is no tamper. Its duration is also consistent.
What you cannot confirm from the video is that it was not a composite image. Slow speed analysis would show its development.