'The Flash': Who Is The Man Behind The Iron Mask?

When the team on The Flash left to travel to Earth-2, I had a lot of questions about what happened. I wrote a whole article on it, so check that out HERE. What I did not expect to have been right. I thought Harrison Wells and his daughter, Jessie, might come back to Earth-1 to escape Zoom. I was right, and that was revealed in the latest episode. What I could never have predicted was the string of events leading them there. Jay died, for one thing. However, that isn't the most interesting part of the show.

This fellow in the iron mask was trapped in a jail cell across from Jessie and Barry. He never speaks, and they communicate by tapping in a five tap code created by prisoners of war. What he manages to tap out is the word 'Jay.' Barry then says Jay Garrick, the other Flash who is on Earth-1 helping the rest of the team out. However, when Barry explains that Jay is on Earth-1 and isn't dead, our mystery mask man reacted rather largely. He bangs on the glass and shuffles a fair bit, so the question then becomes: why did he react this way? Why did he seem so frustrated that Barry didn't understand? I have a couple of different theories about who he is, so bear with me.

1. He's Jay!
Jay Garrick isn't truly Jay. He wears the outfit, but he doesn't have his speed because he never had it. Instead, he is posing as Jay in Earth-1, biding his time so he can learn how to be given speed. If that were to happen, Zoom would be able to become even faster without stealing from speedsters. The mask is on so he can't tell anyone the truth.

2. Iron Mask Knows Zoom's True Identity
Perhaps they were once close. Perhaps they were family. Maybe our mystery man is an alternate universe version of Zoom. Maybe he knows the truth about the power stealing? Maybe Zoom is a power mimic and if he kills iron mask, he can't steal speed anymore. Maybe the power mimic is iron mask and Zoom has another use for him.
3. Iron Mask's Power Is Voice Related
Iron mask is unusual in that he communicates in taps. Jessie and Barry are able to speak to each other so obviously their cells aren't insulated to the point they can't speak. Perhaps iron mask's is because of his power, or maybe he can't speak because of his power. We know there are those who can't speak because of their power being linked to the voice. Black Canary in many instances has the power of the canary cry. Banshee has a sonic scream. Most of all, we have Black Bolt who can't speak because his best weapon is his voice. However Black Bolt isn't DC but Marvel, so it can't be him. However it can be someone similar.