My first AGR card with MBNA had the wrong account number on it. When I applied for the card, I gave them my existing Guest Rewards number, but they processed it as if it was a new account. So, I had two AGR accounts for a brief period, until I was able to get it straightened out. My "new" AGR account got some bonus points for signing up as a new guest rewards member, and they even transferred those points (as well as points I earned with my credit card) to my old account.
They didn't send me a new credit card with my correct AGR number until a couple of years later, when the first one expired. That only confused one agent, who was going to enter the incorrect number on my reservation when I gave him the credit card.
So, anyway, my Chase card doesn't have my AGR account number on it either. It doesn't bother me, though, as long as the account is correctly connected. Having not received any "Welcome to Amtrak Guest Rewards" package in the mail, I presume that it is correct.