My suggestion for high temp jb Weld still applies. Clean the crap out of it and JB Weld about 1/2" past all sides. Your compression #s indicate the important seal is good and with no crossover of oil/coolant (can use test kit to confirm), it looks like a minor leak from outer edge oil channel. The wrinkle looks more like an imperfect torque pattern caused a bunching up.

__________________
2011 E70 • N55 (me)
2012 E70 • N63 (wife)