I inset some screws to install some door molding (base) and wish to fill
the holes with something that is non-caustic as possible. I will paint
(Zinsser 123) over it. At least one product I looked at contained
Formaldehyde--and that chemical and are not on speaking terms. Perhaps
there is a suitable caulk?

I only have four or five 3/8" holes to fill so I don't want to make a
mountain out of a molehill. But I would prefer to avoid any
"outgassing" too, or issues when the inevitable day comes that I need to
drill the substance out.

Thanks,
Bill