It's taken my submissions (17 so far) anywhere from a week to 5 weeks to receive the registration stuff. In the past all that was sent were serialized dogtags, then they let you select a shirt or a pouch, now its been a hat (along with providing proof of purchase for the $200 store credit). To my knowledge the Omega (rifle can, not pistol) has always included a muzzle device with registration. I registered two Omegas and was able to pick between flash hider/muzzle brake, and thread pitch/bore size for each.
To the poster still waiting for their pouch, call customer service and they'll get it sent out to you. From the time frame you indicated I also had two registrations that didn't register in their system and they were happy to send out the pouches with basically no questions asked (other than to verify the serial number of your can)!