A complex number is actually a 2-dimensional thing, composed of real and imaginary parts. So it makes no sense to talk about a one dimensional distribution for complex numbers, and chi2gof seems to work in one dimension. That means you need to find a goodness of fit test that applies to multivariate probability distributions.
Think about it. Are the real and imaginary parts of those numbers correlated? Even if not, these numbers live in a 2-d vector space, the complex plane.