How many ancient megalithic building sites used a form of iron or metal "staples" to hold large stones togethe

I've seen on TV in South America the ancient indians, I think, in Peru used metal bars much like what's shown in your link to hold blocks of stone together.

These in South America were made of a Nickel alloy and required a furnace temperature that was not achieved in the western world until the 1930s.

I think you will find that at most, probably all, of these sites, these 'metal staples' are not contemporary with the stone structures but were added in the last century or two in early attempts to preserve and stabilise the structures once it was realised they were of archaeological and historical importance. This is certainly true of the European megaliths which were built during the stone age and I believe the only metal the ancient Egyptians had were copper and gold, too soft for use in construction. The early builders of the stone structures you list were expert engineers and craftsmen and would have had no need of metal reinforcing to hold the structures together, even if suitable metal had been available which it was not.

You can confirm this by contacting any school of archeology at a university.

The staples in that link are clearly bridging a gap caused by subsidence – obviously fitted later in a clumsy attempt to restore the building. If stonemasons of the skill of the original builders needed to use staples they would have developed a method to hide or disguise them.

I didn't even realise that iron staples were used like that in the ancient world. And your link shows something else I never knew, that dinosaurs and man coexisted just like in the Flintstones.

If I didn't know better I'd think it was an attempt to discredit science by people who don't have enough faith to think that God is stronger than science.

You could say the same for stone carving. It is surprising that they developed the same methods around the world... It is not pure chance, it is coming up with the same logical method to build large monuments. Nothing surprising about it.