I washed my Space Leopards army in Gryphonne Sepia and then ran into the same problem you have. Fortunately, I used Seraphim and it looks the same, but make up your own mind. Below are Pictures of my two dreadnoughts. The one with the HUGE pole arm is Gryphonne, the lasccannon/missile launcher is Seraphim. To me, close enough, but like others said, check yourself! (both of these are washes over averland sunset) I am no genius painter, so claim no great color/hue recognition.
Gryphonne
Seraphim