AH WAIT....I SEE IT!!! In the original picture, the green and orange are hooked together...count all the squares. The orange is missing a section. Where the green has 3 blocks, the orange only has two and THAT explains the missing piece when they shifted everything.
Actually, this is the easiest to answer. The orange piece in both pictures has the exact same amount of squares.
It's the displacement theory. (Well, that's what I call it. I really don't know the exact term.) Do you ever buy something from the store, want to return it and even though you think you put it back in the styrofoam packaging correctly, it
never fits back in the box correctly

, or there is an extra do-dad of styrofoam, that you don't know where it goes?

It's kind of the same, when you toss polygon objects into a box or jar and you have to shake or rattle it to get everything (that in a certain
order fits,) to settle into the same space.
In the first picture, the two greens & the orange are all
stacked. People assume that when it's rearranged, it would still all fit together. But the red triangle is actually longer, so, no it doesn't all fit when you
unstack the green & orange pieces.