Since you did not actually call a ball, it's not a made ball, table is open. You did not call a shot (as in 5 in the side), you called a safe. Although I think in TAP rules if you make a ball that way that is what you now play.
In NON-Call Shot play if the table is open and you legally drop a ball that is your choice and You Continue to shoot. But in Call Shot you can not claim a choice on a Called Safety.