I'm not sure if you've seen this yet, but
these posts show that DarkstoneShipping was originally going to be Gold x Pearl, presumably under the assumption that Dawn would be the basis for Pearl instead of Barry. The reason given in the post is because "they both have dark hair and are percious stones". The submitter also stated "i like obious ones!!" which is hilarious, considering we're having this discussion in the first place. Regardless, the name for Gold x Pearl today is HotBloodShipping, which is included on the archived October 15, 2011 update of the list. I can't find any earlier mention. It is worth noting that the original post was from July 18, 2006, the Diamond and Pearl games and anime didn't launch in Japan until September 28, 2006, the earliest mention of Darkstone shipping for Gold x Platinum is from
this thread on October 30, 2008 as "Gold x Platina" (and only mentioned as one of the "worst" and "creepiest" pairings), and the volume that introduced Platinum, Pokémon Adventures volume 30, wasn't released in Japan until December 25, 2008.
Hopefully some part of that was helpful.