I also have a Archer rank 14 but have not tried to use Archer WS with javelins.
I don't believe Archer WSes will work with Javelins. In fact, I don't believe any WS will work with any class's throwing weapon.
Kudos to SE for implementing this amazing thing and making the Lancer class that much cooler.
I hate to burst your bubble, but every DoW class is supposed to get some kind of throwing weapon. According to the official FFXIV site, Pugilists get chakrams, Marauders get throwing axes, and Gladiators get throwing knives. As an Archer in closed beta, I had to throw rocks when I ran out of arrows, although those never showed up in my inventory; the throwing weapons for other classes go in the same pouch fishing bait goes in.