The years from about 1928 to 1932 were sort of an uncomfortable interval in the development of atomic/nuclear physics. The physicists concerned knew something else had to be going on in the nucleus. The idea of having the electrons serve to counter the mutual repulsion of the protons didn't really work out well in detail. By 1928, a calculation with the Uncertainty Principle was telling them that electrons couldn't be confined in a volume that small anyway. And the model of beta-decay as an ejection of a "nuclear electron" had interesting problems, one of which led to the proposal of the neutrino. It came as something of a relief to find the neutron soon after this (though how that helped would take a while longer to understand...).

So perhaps it's not surprising that writers were using all sorts of ideas, while feeling the ground of scientific theory continually shifting under them.