Olive Leaf vs. Oleaster Leaf
Perhaps it was not an olive twig, but rather a stem of
oleaster, lokh, that could have easily been mistaken
to be from an actual olive tree.
Oleaster is present in Armenia today.
Consider also that Noah was 501 years old when
identifying the twig so maybe his eyesight was failing <g>
or he did not know today’s scientific name
ArcImaging - The Search For Noah's Ark