There must be two different recordings?
Mine, passed down by my Great Aunt's “lady-in-waiting” (I think that there may have been a different relationship?), was definitely G III, not G V.
He was muttering “king's cross, king's cross, king's cross…” repeatedly, rocking back and forth, before any of the other contestants had completed their turn.
And before anyone dismisses this as pure conjecture, there is absolutely no proof that parts of the Northern (and Metropolitan) lines were not already operational, on a limited or “bank holiday Sunday” schedule.