The Flash Season 2: 7 Theories On The Man In The Iron Mask's Identity
2. Some Version Of Jay Garrick
The name Jay Garrick has to mean something. It can't just be a name that Hunter Zolomon plucked out of thin air, not when we've had Henry Allen mention that surname, not when Zolomon's dad was called James, and especially not when the character is such an iconic one from the comic books.
There are 52 potential Earths in play here, one of 'em could have a Jay Garrick! If the character does indeed exist, I'd still say the most likely option is that he's an Earth-2 version of someone on Earth-1, even if they go by different names (again I mention Henry Allen here, though I guess Wally West could also be their Jay Garrick).
If that's not the case, then it's still plausible that Zoom took Jay from Earth-3 or wherever, and given we've already apparently seen that Jay does not exist, that's why Hunter wouldn't be believed, why he looked like Teddy Sears from the back, and why he tapped out JAY.