Well, if you're gonna troubleshoot a leak, and you have enough patience,
then you apply water to the lowest suspected elevation, and check for leaks.
You progress higher and higher, until you score. Of course, you might have
leaks in two places, etc.
"Goedjn" wrote
Wait until everything dries, and ppour a bucket of water
into the valley. If it ends up inside, then that's where the leak is.

Drill a 4" hole in the lowest part of that valley, and install
an internal drainpipe.
You gotta be kiddn'
This is why only people with more
"artistic" sense than common sense build roofs that way.
Fix the damn leak!