I have a 2008 X5 3.0si and I recently removed both lower engine covers to inspect for an oil leak also and I think I might have the same leak area based on your description and your pictures above.

However, first I am going to do the oil filter housing & oil cooler gasket since they are a common leak point and based on the YouTube videos it’s a much quicker/easier job. I usually do all my own mechanic work & but the oil pan gasket replacement looks like a very time consuming repair since it involves remove the front axles, suspension and lower engine cradle. The video I watched showed a mechanic in a independent shop with a lift and he was saying it will take him at least 10 hours to complete. My biggest fear is that I do that work and the leak continues & turns out to be the front or rear crank-seal. I am very tempted to try Blue Devil Engine Stop Leak but I know probably everyone on this site will tell me that is bad for the VANOS system and other seals. I really like my X5 and I know an oil additive is not a permanent fix but how much time and effort should a person spend on a $7000-$10000 second vehicle?