The alternative carrier boards all cost far too much, many more than the Nano itself which violates the first law of carrier boards [0]. Only the OEM carrier board is priced reasonably.
[0] A grocery bag should never cost more than the things that fit in it; a phone case should never cost more than its phone; a camera bag should never cost more than a camera; likewise, a carrier board should never cost more than what it carries.
For 1000 boards, from a distributor you're paying 1000 * $99 = $99000 and you are done with the order in 2 minutes.
To go through the partner program, hiring someone to have coffee and meetings and phone calls with NVIDIA for 6 months = $50000
Will going through the partner programs save you more than $50000?
Or can NVIDIA provide a pushbutton NLP bot that navigates their partner program for you and deals with all the necessary phone calls such that 1000 Nanos arrive at your doorstep for less than $99000?