[WaifuApple]

If the worry is more about taking a charge than the damage itself, the possibility could be that you only move once per attack. While this sounds like a nerf, in the circumstances of this idea it would end up being so that, since the user would likely take the damage anyway by virtue of dodging into a tile still happening and then dodging back into another tile to the same effect, it would leave the user in the same situation but with one charge up.

Alternatively, have it check whether they take damage after dodging, and refund any charges wasted on trying to make an unsuccessful dodge. At least, in this case, it would make cobra users feel less like they're wasting charges for no result. To make it more reliable for them, too, you'd want to at least ensure that they're making the attempt to dodge towards the closest safe tile, to avoid them dodging one tile off from safety and then dodging right back where you started.