This. It seems the only way he can be free of the Oathpact in proper is to have a sufficiently practiced (and sane) Bondsmith reforge it with other souls (or, I suppose, break it open entirely). To get such a Bondsmith, there needs to be Radiants swearing Ideals near Ishar or bonding godspren themselves. To get Radiants, you need to scare the truespren into returning to Men. I wonder how big a role he played in getting Syl out and urging Phendorana and the rest to follow?
It might be more than just a selfish gambit, though. Maybe he figures after 4,500 years mankind had progressed enough to end it for good themselves. Maybe Navani and Raboniel are his endgame.