I’ve sharpened a Kriss style blade before and I used the curved stones. Like yours, the knife had no edge at all. What I found was that the steel was incredibly soft and could not actually hold an edge. I got it much sharper than it was, but it was pretty futile. If the knife you’ve received is made from good steel, you can try riding the edges of your diamond stones to cut the initial bevels in and the refine them with the curved stones and then the strops.
