That does make sense. Moriarty believed that Sherlock had no way out. Moriarty knew what a lot of people didn't fully yet realize. That Sherlock did have a heart, he did care and this was his Achilles's heel. If Moriarty could die being thought an innocent killed by Sherlock Holmes with no hope of redemption then he would have indeed won the game. Sherlock would take Moriarty's place as master criminal and Moriarty would be forever painted as the hero who brought him to heel.
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I think you're onto something here. But I have a slightly different view on Moriarty's motives. He kills himself to force Sherlock to kill himself as well. If Sherlock really knew the recall code, he could have recalled the killers himself, but he needed Moriarty ("I don't have to die if I've got you"). Then Moriarty realised that they are two faces of the same coin, both in it for the game ready to do whatever it takes to win. Except one looks towards destruction and evil and the other towards good and saving people (sorta..). Sherlock really cares about saving his friends and they both know it (Moriarty:"As long as I'm alive, you can save your friends, you've got a way out. Well, good luck with that."). Dying is a small sacrifice if he gets to win the game and have Sherlock commit suicide (and as you mentioned it, with no hope of redemption, since the only two people who could redeem him are dead).