Sound waves do not add on top of each other in a 2 + 2 basis. As you said, SPL is logarithmic, so to reach 2x the volume you need 10x the SPL.

Two sound waves do not add up two 2x the volume.

Once again - I do not know if this translates directly to explosive energy, but I know for a fact this is gospel for audio engineering. It's literally my career.

Here's another source for those who disagree that 2x volume and pressure level = 10x energy