Titanate-zirconates used as piezolectric sensors/generators ase pure ceramics (oxides -- as indicated by the '-ate' suffix). They most certainly are not ceramic metal composites.
Don't know how this impacts your theory -- unless you were were trying to make the logic leap that the presence of ceramic/metal composites indicates the presence of a piezoelectrically fired or fuzed missile. In that case, your theory falls apart. Ceramic/metal composites and piezoelectric ceramics are totally different animals.
All of which rather begs the question... if they weren't part of the aircraft, how did they get there?