Fizz backflip - Veigar Ult

Sorry I was just curious if I could get some feedback on this. I know Fizz's backflip can allow him to dodge ult's mid cast(lel) but I actually finished casting the ult and as it was about to land he backflipped with no damage taken. He finished his e, and then proceeded to w-q-r me all the while my ultimate, which did no damage, was now on cooldown.

Is this properly working? Just curious mostly for future champ selections. Thanks.