Ahh yes,
Firefoot , that would make sense! Perhaps my own internal allusion to similarities with Earendil clouded my judgment a little
Was through the devices of Bombadil that they came to have such an accurate vision - a true and proper foresight of things to come? Or through something about their own hobbit-natures when exposed to his encapsulating words?
I personally dont feel it to be unusual for Frodo on his own to have such moments, though in the House of Bombadil it seems much of the lore of Middle-earth was translated in tale by Bombadil for the ears of all four hobbits. Perhaps it was just down to the magic of ol' Tom.