Maybe nitpicky, but i personally think it is supposed to be Matoro recognizing it as Toa armour. The line specifying it as Toa armour is right after a line that is definitely from Matoro’s perspective, and if it were just for the agudience benefit, Teridax states that it’s a Toa right afterwards, so it could have just said “bits of armour” if Matoro didn’t recognize it as Toa armour. At least, that’s how I read it.
Well, I gave it the name.