I emailed yesterday and asked nicely for the extra 50K. I was denied on the current card but if I opened a new card she would grant me the 100K offer on the new card.
I called instead this morning. Stated I just discovered that when I signed up for the card there was a better offer. He asked for the offer code #. Looked it up and said yes I would have been eligible for that code. I asked if there was any way to get the additional 50K and he said shouldn't be a problem. I was put on hold for 10 mins. He apologized for the wait and said the additional points have been added to my account.
I logged in and sure enough I have the points.
Advice: Be polite and you shouldn't have any problem.
GOOD LUCK!!!