ZIF socket with 0.1" row spacing
As others have mentioned in the comments ZIF sockets are not designed for 100 mil X 100 mil pitch because DIP chips aren't designed like that.

Your use is off-label. So you won't get a perfect solution, but you may look into using a PGA burn-in socket. It'll give you ZIF functionality with a 100 mil X 100 mil grid, though it will always be too large in one dimension for a >2 X 2 pin header.



Your alternatives are:


Follow The Photon's advice and simply design your daughter board to have its programming header as 100 mil header rows separated by 300 mils.
Use a single 100 mil header and tie the rows together on the ZIF socket.
Use pogo pins like almost everyone else in industry and rightly suggested by  Ignacio Vazquez-Abrams.