I messaged the seller last night and he said "My apologies those listing descriptions were from a duplicated listing. Don’t know much about the knife, I purchased a large collection with lots of limited edition buck knives in it. Couldn’t find any information on this one, looks factory to me. Unfortunately that’s all I know." This doesn't help solve anything. The duplicate listing information was in regards to my question about D2 steel and cocobolo handle. I didn't ask if it was factory but rather what constituted making it a "rare" knife.
As mentioned, the grind does look different than a current production 103, but it looks similar to the grind on older, pre date code 103s. The one line Buck with BOS on the opposite side is really odd since as pointed out, these two were never together. It is an interesting knife that I would love to see in person, but not at the price they are asking. I am leaning towards it being fake or some type of odd custom.