OK. I fixed this issue, albeit, not to factory specs. I simply cannot mess with it anymore.
Basically, I verified that the green wire was good to each brake light. For whatever reason, I cannot get current from the WHT/BLK wire to the GRN wire. It simply will not work. So I tied the green wire before the BLFS directly to the High Mount Brake light power source (Also WHT/BLK)
I've semi-permanently wired it this way, however I left everything intact enough that I could reverse this at anytime. Everything works fine, exactly as it's supposed to now. The real cause of this problem is still unknown to me, but consulting an electrical engineer, I decided that this solution was the best.
Thank you for you help and advice. Anyhow, I consider this issue fixed now!