Right now I'm at Walz Tower and I've been trying to learn the Frog Song ability from the Elf Toads. I've assigned Faris as my Blue Mage, but so far I've had no luck getting the toads to use Frog Song on her. Is there any way to possibly make this easier?

Also, along the lines of other Blue Magic spells, are there any in the game that are permanently missable after a certain point? I want to be sure to learn all of them before it's too late.

Thanks!