Cockroft and Walton showed that lithium, when bombarded with fast protons is split, generating alpha particles back in 1932. So it is not inconceivable that a palladium cathode in a lithium electrolyte could potentially exhibit helium evolution inside its matrix.
After considering Pons/Fleischmann’s experience with the meltdown of the 1 cm cube, and the Frascatti effect of neutron generation by plunging hydrogen-charged titanium into liquid nitrogen, it seems that sudden lattice collapse effect might cause transient emissions of particles associated with fusion.
In the case of electrolysis involving palladium, upon being charged with hydride, the lattice expands but does not do so in a predictable fashion and at some time during the electrolysis it could be expected that there would be sudden local contractions in the lattice that could give rise to neutrons. But such a lattice would not have a memory and I’d expect neutron emissions to be just what has been observed – erratic and not reproducible on command, as the metal becomes hydrogen embrittled. What would be needed is a lattice structure that is capable of those instantaneous localized collapses, and then springing back into its original configuration, to be able to do it more reproducibly. What probably happens is that once it contracts in a local area and has a fusion event, it cannot spring back. I might look to involving mercury in the process, since it makes such a crappy hydrogen electrode and might enable higher overpotentials and hence higher effective pressures as calculated by the Nernst equation, increasing probability of alpha emission. Perhaps a palladium amalgam as cathode, using lithium electrolyte. One would then get reduction of lithium, and a mixed palladium-lithium amalgam. It could be worth looking into but the vapor pressure of mercury would need to be considered, were any appreciable heat generated. Else, doping Pd with Hg