If you imagine having a very deep hole in the ground, the longest sight line would be from the lip to the bottom. If you then dig a small hole at the bottom, you wouldn’t be able to see the bottom of the second hole, but only some part of the wall
Similar in reverse, if the pyramid had a false peak (a inflection place where topology changes from steep to less steep), it could obscure line of sight between the real peak, if the angle formed by the line of sight between the two distant peaks tries to intersect the intermediate inflection point
I can imagine some shapes like this in theory, I just think we can rule them out in practice.
For the hole example, we know there aren't any holes 500 km deep. For the pyramids, we know the line of sight is very close to flat (it's at least 500 km long and less than 10 km in elevation change). If a false peak prevents you from seeing the real peak, the angle of the mountain above the false peak is shallow enough that you can call it a plateau.
Similar in reverse, if the pyramid had a false peak (a inflection place where topology changes from steep to less steep), it could obscure line of sight between the real peak, if the angle formed by the line of sight between the two distant peaks tries to intersect the intermediate inflection point