How does the text imply the sons of Elronds' choice, one way or the other?
[Edit: and I don't want to be too hard on Foster here, but even going with the source material he had he does seem to have published some rather unorthodox opinions. Compare Tolkien's notes in AoTB on "The Sea-bell," specifically on its authorship, with Foster's entry. Tolkien says that it's "highly unlikely" Frodo himself wrote the poem, while Foster suggests that maybe a Fairbairn found a lost text later on and inserted it into the Fourth Age editions of the Red Book. This is all fine and dandy if you're writing
fan fiction, but not for a reference work!]