Idunno. It's interesting, but I don't think I buy it. This feels like a "Sometimes a cigar is just a cigar" moment to me. The ceiling is 20 meters above the ground, with 34 individual frescoes. The fresco in question "God Divides Light from Darkness" is admittedly, one of the 9 large center panels, but these 9 panels are also at the highest point in the room . The figure in question is one of 343 on the ceiling, and one of many that depict "God".

Even if that picture of God is 2 meters tall (slightly larger than life-size), which I doubt it is considering there need to be 343 figures on 567sq meters of real estate along with backgrounds and other art(rough estimates, I didn't include the sides and I don't know what the wikipedia article includes in its cited size for the "ceiling").

You'll have to excuse me if my skeptic-radar goes off when you're telling me that Michaelangelo put a "secret message" into one of the many frescoes in the chapel (this is the second one people say they've found regarding God and the Brain, the other being "God Creating Adam" supposedly having some sort of depiction of the two hemispheres of the brain), an anatomical drawing in the shading of a 2 meter God's cloak and throat, which I'm supposed to be able to see from 20 meters away? That's 65 feet and change for those who still run on imperial. How much detail can you see on your friend from 65 feet away?

I'm sorry. maybe I need a stronger brand of tinfoil.