These are the guys that had him in capture:
https://en.wikipedia.org/wiki/Haqqani_network
Not the same thing as the Taliban which was kind of the assumption everybody was going with. The Taliban got the 5 commandos, the US their guy. Haqqnis.....nothing attributed to them. Unlikely they would keep the guy for all this time and then take a pat on the back as their compensation for letting him go.
This is their game, from the wiki:
So it's probably a safe guess that their side of the deal was cash. But of course it wouldn't show out being through the US in any case. It's not like they wired them the money straight from Obama's personal bank account. They would have somebody in the Middle East pay the money, and figure out some way to kick it back/a favor back that nobody would notice. Or use something like diamonds that the Haqqanis could easily sell.