I had heard about the incident but never read about it until now. Your 4th point seems explanable if you consider that not every "expert" has an abundance of expertise or common sense. Yeah, they were on the bomb squad, but I'm sure their 76 years of combined experience wasn't all in explosives. Add in the fact that they were determined to be inert.....
The missing grenade, I'm guessing a deputy took it prior to the mishap and is now very nervous about getting caught given the ongoing investigation.
The missing grenade, I'm guessing a deputy took it prior to the mishap and is now very nervous about getting caught given the ongoing investigation.

