Unhappy [Q] Virgin Mobile S3 Bricked? Trying to go back to Stock

So my Galaxy S3 for Virgin im guessing is bricked. I first had rooted and flashed to a Kitkat rom but now im trying to revert back to Stock and completely unroot it as if i had never done it. I looked online and found a "fix" where i used odin to flash back to stock, but that didnt work and it failed so now im stuck at the screen on my phone that says, "Firmware upgrade encountered an issue. Please select recovery mode in Kies and Try again." the thing is Kies wont recognize my phone. someone please help