I used Ceratec in a compressor not an engine that was MoS2. I could see the Ceratec in the sight glass so I pulled the side cover and cleaned it out and changed the oil.
The stuff in the oil pan I found when I changed the rusted pan otherwise I would have had no idea it had fallen out.
The greenish grey stuff is MoS2 and no it did not mix back into the oil when the engine ran, the engine ran 2 hrs before the pan drop, the oil was still warm. The chunks are pieces of gasket from the tube that got knocked in taking it off.