In theory.. YES
You would have to have a large enough colony of the suspect Palythoa that had been abused/agrivated and thus capable of filling the water column with PLTX for any possibility of it happening and i would think the chances of it being aerosolised even then would be very small
So the chances of it happening although not zero are so low as not to be of any real concern
Personally i Just avoid the Palythoa like Grandis,Trash polyps etc (like in the picture) as these are the ones that always seem to be the culprits when incidents with PLTX have occured
Enjoy your Zoanthids, one of the prettiest corals we can add to our reefs