Everything I've seen has the DSA (trac-lok) *included* with max tow option. I did the build & price on Jeep.com and also using the google spreadsheet shared on here. Perhaps the DSA option is specifically reserved for the non-wide track axles? That was the order code for it when I got my JK.
I believe it all started on his (first?) forum that was for Jeep JKs - that's the first I heard of him. He pissed people off by deleting posts and/or banning people for talking about products made by companies that were not sponsors.