It actually doesn't really matter if they fit or not, NZXT cases mounting points for fans are not accurate. The only fans that will fit in a NZXT case are NZXT branded fans.
For some reason NZXT fans are smaller than the standard fans, and the holes will not align.
any of the NZXT fans will fit, i would buy matching ones to whatever came with the case.
I am glad you posted this here, as i ran into the same problem trying to put in couple of other fans that i had lying around.
source: i have an NZXT phantom.