Just thinking out loud - A few years ago when the pin protection was added to the movie channels we were dumping the nvram from Pace 4010's and Samsung 2100's and putting back amended dumps if I remember correctly. If we did this again and compared a few from the same model box would we be able to narrow down where the info we need is? And is this something that existed on the older firmwares or is it newly implemented on 3.7 ready for N3 cards? I presume the RSA key is individual for each box in the same way as a boxkey so even if this is possible this would only be functional for those with an N3 card in an older box.
Im guessing it will be pretty much impossible on any of the newer boxes to get the RSA key even by chip removal ? Even though there were some false dawns no-one ever managed to get a bk from a Samsung 2110 so I cant think it will give up anything else.