Who's this "Miss Information"?

And when you trap a xenon inside a C60 cage and start stuffing other things in there, the chemistry gets really weird.

I mean, it's in the column. Close enough.

And what happens with iron ?

Close, the maximum binding energy per atomic mass unit is iron-56, but splitting heavier atoms does not guarrentee releasing energy. If you consider the graph of specific bonding energy against atomic mass, then also consider that you need two numbers that add up to the original mass, it is clear that you need approximately more than 100u to release energy on fission.