Could this be my problem with my paint? Does this look like these can caps for pouring have silicone on them?
Silicone will definitely cause problems with paint, get a car with a bunch of amor-all sprayed all over the interior or especially on the tires, then paint a fender above it and guaranteed to have problems. With the pic it could easily be something in the plastic lid, an actual chemical in the plastic, a mold release agent that's wicked into the plastic etc. And it is possible to transfer that to the paint as your using it. .