IIRC, the placer can't break their own blocks (not glass, as that's been changed to be its own separate block with its own recipe) if warded unless they un-ward them first. Also, the mana lens would have no interaction to tell if it could move them, even if the placer was the one to use the mana lens.
Isn't there craftable warded stone, though? I seem to recall that being a thing (then again, it's been awhile, it's 6 in the morning and I've been up all night, and Bo-bobo, so I could very well be wrong).