Statistically, from others on the VJ Journey, including us, only about 50% of the "Request a SSN" from the CR-1 paperwork ever go through. The officer that admits you to the US has the "option" of clicking a box on his/her screen to send your info to the SSA office. We had ticked the box to request a SSN, and when we inquired, there was no record. I even specifically QUESTIONED the officer when my spouse came in to make sure the box was ticked on his system. NOPE.
So the fact there was nothing in the system means your officer at secondary did not make the request. Unfortunately, this is not unusual. Hopefully you'll be on your way soon!
Sukie in NY