Well with some experience with ky, i can give u a couple pointers
if the ky player is spamming fireballs and u cant get in then either roll and punish or go for IAD pin. IAD pin is really helpful because if he trys to AA, fireball or w/e they get countered and u get free dmg. Use j.d if they jump around alot. It will be good to HS disc here and there to claim some space if they run from you alot. Basically if u cant get ur way than try to go for a knockdown either by air to ground (i.e IAD pin into j.p 2k 2s 5hs into 2d) or by 2d and 6HS then go for disc setup which can change the tide for u. Also watch for his FRC on the stundipper, kys usually throw after that or go for preasure strings.
yea thats basically all i know i hope someone else can give better and more specific strategies on ky