for the sake of argument, steal and animate effect will not trigger the ability to spawn a creature
even thematically steal and animate arent destroy effects
you can argue even replacing a weapon in the current weapon slot with a new one is considered destroyed but thats not the case now is it? (or else DG wont even exist)
however the coding might implore otherwise but i dont know the exact coding, do you?
in any case, it will only spawn a creature when certain condition is met, as explained in the 'Notes' section
one thing though, i'm not sure if i should include killed as flying weapon = destroyed
but if i could, i would intend it to be that way