How do you know?
Based on the pictures of the aftermath.
How it exploded. What’s left.
TNT doesn’t handle resistance well. It blows using the easiest path for the energy.
There’s a lot more to it. A whole college course but that’s what it looks like to me.
Also there is an expire Explosives License in Warner’s name.
A pic floating around on Parler.
I assume it’s for mining or a mining company.......if so, if true, he would have been very familiar with TNT.