Where is your evidence for your claim? Doctors and children are among the dead.
"Doctors and children are among the dead" isn't inconsistent with "this came from an order of devices specifically for Hezbollah" (it does cast doubt on "this was a precisely-targeted attack on Hezbollah combatants", but that's a very different claim.)
Without taking in consideration that "Hezbollah" as a loosely defined group ranges from conservative politicians and institutions to bona fine terrorists.
These devices were being shipped in equal measure from the guys sending rockets to Israel to the local equivalent of those preppers who like to spend their weekend eavesdropping the police radio waiting for WWIII.
Unfortunately real life is a bit messier than a Tony Scott movie, and we didn't harm 5000 evil terrorists ready to destroy America and Israel from their Cobra underground lair, just a bunch of random people - a few of them genuinely bad guys (how many? thousands? hundreds? less than ten?), and everyone else who may or may have not sympathized with a group that may or may be not considered a terrorist organization, depending on who you ask.
Are you claiming that these sources are wrong, and Hezbollah actually bought them from some retailer who happened to have 5,000 units of tampered inventory?