If anyone knew that the kid's father wouldn't just hand him over, it was Nick. He also knew that mortal weapons and superpowers weren't gonna get the job done. To take out a god you either had to be a god, or have a god forged weapon. Long before any of this Hammer S.H.I.E.L.D. bullshit, Fury had anticipated the day he might have to square off against a deity for the guy's son. He came prepared.
Which, as it turned out, with the addition of Thor to this operation, S.H.I.E.L.D. was prepared, too. Nick didn't know if that was just a happy coincidence or if someone deserved more credit than he was giving them, and he didn't care. The mission was covert and the team was small, not just for the element of surprise but because what they were doing here wasn't supposed to get out. Fewer people who actually knew about the Cube, the better.
USAgent took point, and on a three count he busted his way through the front door and whatever awaited them inside. The others could handle the angry god, Nick was gonna find the kid and that damned Cube.