Dennis,
Since N2O is a an oxidizer and not a flammable, and the bottle would have to be rubbing on the cement a very, very, very long way before it would even begin to wear a spot on a steel bottle like that (let alone a hole), I find it very, very, very unlikely that an explosion would occur. You may see or hear a hissing noise as the pressure is released momentarily and quickly. But when they tell me it's illegal, I'll worry about it then.
The bottle is DOT approved and no matter where it is mounted outside the frame rails, it has the opportunity to rub on the ground . But if the bike were to be skidding and perfectly balanced on it's hind quaters for that length of time so that it could rub the ground, the bottle would do nothing harmful even if the top valve happened to be knocked off.
I would be more worried about my gas tank breaking open and fuel going every which way before I would worry about those bottles.
But nice try you turbo guy you.
Guy