When MacGyver puts on his "suit of armor" the legs are pulled tight in back and wrapped to the inside of his leg. In the next scene as he heads out the gate, they are pulled tight in back and wrapped to the outside of his legs.
The ants produce a cacophony of squeaks and shrieks. Ants do not have vocal chords and so cannot make these sounds.
When MacGyver, Alden and Trumbo discover the valley overrun by ants, Alden takes a couple of close-up shots of the ants with his camera. There is no (regular) camera/lens in existence that can get this close to something so far away, and certainly not the one he's using.