Super simple. Just make it so that they can only deal status to the player if the charge attack hits a monster. This way you don't get screwed over if someone takes the last kill in a section or if you get a lagspike and end up attacking a wall.

Self status chance would only activate if you did damage.
Kind of like the Pokémon Move Double-Edge.... you deal a lot of damage but you end up taking damage WHEN you hit. If you miss no one takes damage.