So you have the hint there identified, I think you have it misdirected.
"If (Preservation) has not returned, then has, perhaps, someone else taken up his power to use in (this fight)? Is that not what your teachings say will happen? That which has been sundered must again begin to find its whole."
The secret mistborn history tells us of someone who took up the power of preservation before it made its way to Vin, and then to Sazed. I'm confident this line is a nod to whats happening behind the scenes in the cognitive realm.
