Help me out here: what is the difference between Hydrogen Flouride (from the article) and Sodium Flouride (from my toothpaste - that has a warning not to ingest it)?
Same difference as there is between sodium chloride (common salt) and hydrochloric acid (muriatic acid). The big difference is that fluorides like NaF and HF are respiratory poisons, while chlorides are not. So HCl can burn you, corrode your lungs, etc., but it won't poison you.
HF is more dangerous than NaF because it's not just toxic and corrosive, but it can also as a vapor attack your skin and lungs. And because it's a respiratory poison, it knocks out your nerve cells, so you don't even feel it, for a couple of days. Then it hurts like hell for 6 months, since HF burns take forever to heal.
There's nasty stuff, truly nasty stuff, and HF.
Everyone else seems to have covered acid/base/salt chemistry well enough to answer your question, but I'll throw my two cents in. The difference between hydrogen fluoride (hydrofluoric acid) and sodium fluoride is that exposure to large amounts of sodium fluoride will make you sick and cause fluorosis, whereas exposure to large amounts of hydrofluoric acid will turn you into a large puddle of goo :^)
It's very nasty stuff, as I'm sure you've realized by now, and hopefully they'll find these canisters before the folks who took it get into trouble...