Don't be surprised if you can't remove the smell. Synthetic materials will continue to offgas for some time after manufacturing, and sealing them up in plastic just prolongs the stink. It's the same as new car smell, new shoe smell, new carpet smell, etc.
It will dissipate over time, however. Eventually it won't smell anymore. But exchanging it for a newer mat won't help--you'll just start the process all over again.