The last rays of sunlight were just fading when Les at last thought it would be safe to emerge from the underbrush. He knew of Elves, of course: their brightly-gleaming spear-points, their swift-flying arrows; had not such an arrow grazed the thorny skin of his left arm not half a week ago? But he fled, and hid from their notice, and survived. Les had always been a survivor, choosing not to live in proximity to the other ettens that were his kinfolk. He lived alone, always assuming he would die alone, and he was at peace with it.
But there was a spark in this etten that most others of his kind did not share, and it was this spark that caused him to creep from the concealing bushes when the Elf woman had departed. To his eye she shared the same terrible ferocity of her people, and that was all; could the etten discern any sign of the sadness that enveloped her? I think not. But this Les did see: the door carved in the stone had not sealed behind her when she departed, for a bit of rock had lodged itself in the crack! His fingers could not fit in the space, but hunger and greed (and that unusual spark of curiosity) gave to the etten the surprising gift of insight, and he was able to wedge a sturdy branch into the crack. With that he levered open the secret door, and passed beyond the threshold.
But for all his brief wisdom, he failed to do that which would have saved his life and permitted him to return from the vault with a shining bauble that might have made him the envy of his kin, should he have returned to them with dreams of becoming chief and leaving the solitary etten-life behind. The secret door, now free of any hindering obstructions, closed behind him. Without any knowledge of the opening words, Les would die alone beside the treasure, the last fire he managed to construct outliving the tragic etten, given life by the ageless magic left in the vault.
At least... that's how I see it.
MoL