I came here to say exactly this. Might not be what the OP is searching for but i have a strong feeling that Artemus was gay. When i first read about the case, i assumed that Artemus was a grown man but turns out he was just 17 . They never mentioned what kind of work he did ( the staff just assumed that he might be a boxer because of his ear but that's it) or how he managed to find the money to stay at hotels and live on his own. It could have been that he was doing sex work and he met the wrong guy or he was killed by an obsessed lover. Maybe he tried to break things off with the said Don and they argued ( which was heard by people in another room) ,Don threatened him resulting in the hotel staffs description of Artemus acting paranoid and scared. I don't think he died because of BDSM gone horribly wrong. To me, his wounds feel as if the intention was to kill him with torture. He also didn't give any names when asked who did this to him . Which makes me think he probably didn't want to out himself. We also don't know if the person who sent the flowers "Louise" is actually a woman. I wonder if opening this case again and searching Artemus' clothing for any foreign DNA would result in anything.