Update: I sent a SM on 1/8 asking where my points are. I received a boilerplate response saying they would investigate my eligibility for the offer and send me a letter via USPS within 10 business days letting me know what was found. I responded that my question was not about my eligibility for the offer, which was never in doubt, but about where my other 25k points were. Their response to that was also some boilerplate thing saying they understand my concern and will notify me via mail of the outcome of their investigation. The following day, the other 25k points showed up as pending! Almost seems like it was too easy, but hey, I'm not complaining.

My girlfriend, however, received a response to her SM in which Amex asked for an offer code. Not having anything official, she replied that she has a screenshot of the offer and doesn't know where to find the offer code, so could they please point her in the right direction. So far, no extra 25k points in her account, but I'm optimistic after getting my points credited. Will update when I have more information.