I never really did white water kayaking, just "sea"-kayaking on lakes.
Honestly, like in any other fresh- (as opposed to salt-) water scenarios, I never had rust problems on VG10 blades whatsoever. So I just carried an Endura 4 or my CE Delica. Now that I have an SE Endela, I guess that will become my kayaking knife.
Top three going by pocket-time: Endura 4 in VG 10/Micarta-scales; Stretch 1 in VG 10; Endura 4 in HAP 40