I don't know how significant this information is, but I thought it would be best to mention it just in case someone needed to know:
I have a Japanese version of Heart Gold and am attempting to RNG on it. Unfortunately for me, I don't understand Japanese, so I didn't know which Elm responses were which. However, I was able to figure out which of his responses were which because of the punctuation in each response. When he is talking about Kanto, there is 1 exclamation mark in his sentence(s), when he is talking about pokérus the only punctuation is a line of periods at the end of his speech (.....), and when he is talking about evolution, there are a total of two exclamation marks during his speech. For Anybody who has a Japanese cartridge or ROM, here is how I deduce which response is which:
K = !
P = ...
E = !!
Again, I don't know how relevant this information is to the general community, as most people have an English ROM/cart, but I thought I would post anyways just in case.