I take it Bart Ehrman followed a similar path...learning Greek in order to learn New Testament "scripture"...only to find out that nobody knows for sure what the "original" really was.

This is a common problem for all the Abrahamic scripture-based religions, whether they admit it or not (they mostly don't.) It's really, really hard -- I would say impossible -- to prove that variations or changes have not been introduced since the time of a hypothetical original text, copied from handwriting scribe to handwriting scribe. And the harder, fundamentalist versions of the Abrahamic religions always ascribe HUGE importance to the integrity and wonderfulness of the text.