Here we have Sentinel Prime looking for the pillars, what's the problem? He's going the wrong way. How do I know? The other side of N.E.S.T is a huge door. It's not on one of the sides of N.E.S.T, the sides of N.E.ST are just balcony after balcony. So what does this leave us with? Maybe they gave Sentinel the pillars? Maybe, just maybe. Because I doubt Sentinel turned around, made more destruction, opened that huge door, and took the pillars. PLUS how would he of gotten them on top of his roof like that? With human assistance of course.