Yeah this really sucks to hear, especially only 2 months out from Eiyuden.
Similarly, while I enjoyed the likes of Final Fantasy and other series, Suikoden always meant more to me than those. It was probably the first RPG series I really fell in love with, and in some ways I've always been chasing something that hits the same as it did.
I hope Eiyuden finds immeasurable success and if there is some kind of afterlife, he's able to see it from there. RIP.