When you are using "on touch" you are picking only the object you touched. So when you are trying to compare 2 objects, its not finding the second one because it wasn't picked (or filtered by what you picked).
So what you want to do if you want to use "on touched" is to add this line
On touched object - Sprite
store which frame this particular sprite is on (tempVar = sprite.animation.frame)
then in a seperate event
pick by evaluate (sprite.animation frame = tempVar)
this will check which frame the touched sprite is on, then go and pick all sprites whose frame = to that temp var.
its cleaner if you put this all into a function as well
On touched object - Call function "PickSameFrameSprite (sprite.animationframe)
on function "pickSameFrameSprite"
pick by evaluate: sprite.animationframe = function.param(0)