If anything, the universe seems to indicate that anything is possible in the multiverse, and that everything that is possible happens somewhere, mayhaps just in a locality we dont have access to. That being said, swapping an elementary particle like the electron for a proton made of quarks would involve corresponding changes to the way the forces worked, which might require a different spacetime geometry, or extra dimensions to make the math of the vibrational modes work. So, that's the most complex way I could think of to say there is no way to prove a negative. And those are all the words I know.