What's up with Fiora vs Kled

I have never met this interaction before but, as fiora if kled is an attack away from dismounting, the vital that you hit doesn't count. this is completely unfair if this is meant to be. 5/5 times I tried this in my match today my passive and my ult vitals never worked when ever he dismounted, the q or auto would hit him but it just wouldn't pop it, only hurt him. now you can say I missed it, but that is not the case either. a fresh ult still did not count for a vital being broken when he dismounted. I would hope that this is a bug and not how this match up is played