$$$$ suggests that someone thinks there is something important to learn.
Your own guesswork.
It was recently explained in an article in AW&ST that Boeing is working with Ethiopian and insurer to come up with the best fix and a lot of engineering work is required.
Even though the investigation is ongoing I doubt (and I am sticking with it) anything new will be learned about the fire since there would be plenty of leaks by now.
The 787 haters must wait for something else ...