Here a citation of a follow up paper contained in ICCF15 [...]
Well, first, it's not Iwamura's work, and second the authors admit the results are not definite.
Anyway, by "followup", I did not mean simple repetition. If I remember correctly, Iwamura has reported some results after the 2002 paper, but they are essentially the same experiment trying to increase the rates. By "followup" I meant some sort of orthogonal experiment to improve the evidence. For example, he could try to transmute some radioactive isotopes. This would a million times more sensitive and specific than trying to identify stable isotopes by mass spec. Or, since he claimed energetic alphas were involved in producing the reactions, he could try to bombard the same foil with alphas in a wide range of energies to see if that induced similar effects.
His first report of these experiments goes back to 1998, reported I think in the most detail in 2002. Since then he has reported the same results repeatedly, with essentially no progress, and (as I recall) only one subsequent experimental effort with more or less the same claims. This is highly uncharacteristic of discoveries of real phenomena, but fits very well to incorrectly interpreted artifacts, which is almost certainly what this is.