By brown area, do you mean to the bottom right of the green area?
If so, it may have been accessible due to a bug causing the wall run to function without the ability collected, which I believe should be fixed now.
This area.
Rad, thanks.
That was the one I was thinking of.
It shouldn't be possible to get there now that the wall run bug has been fixed, but also I've stuck a blocker on the path there just in case.
I've also made some tweaks based on the other issues you raised.
