How can I straighten pipes behind a wall?
Can you cut the wall on the other side of the pipes? That might let you get at them without breaking the tile.

Be aware, however, that if you do, it may not help - if the pipes are at an angle, and you straighten them out, you're going to end up with the pipes wanting to come out at a position slightly to the side of where they are now. In other words, the holes in the wall and tile may no longer be in the right position. You may be able to flex things to make this work, but not necessarily.