I think the most likely scenario is going to be voltage induced through the windings in the power supply transformers and possed on to the circuit boards from there.
“windings in the power supply transformers and possed on to the circuit boards from there.”
Not really possible. There is a lot more to it than merely being in the same space together, not to mention a lot of additional circuitry that prevents such a thing. EMP simply is not strong enought to induce EMF in a transformer.