SyEng,
We already have several reasons, HF mostly, why having left the TL#2 where it was (in view of the TR#2 being locked out) is not totally implausible.
A mechanical failure (or an electrical one) has also been postulated repeatedly.
Your post at least has the merit of describing the mechanical arrangement in more detail than I've sen before. Do you have any diagrams you can post? A picture always says more than a thousand words.