This is for Intel 64 and IA-32 Architectures Software Developer’s Manual, Order Number: 325462-053
US January 2015. Page Vol. 1 5-29.
5.19 64-BIT MODE INSTRUCTIONS
MOVZX (64-bits) Move doubleword to quadword, zero-extension
In fact 32 to 64 bit zero extension isn't supported as per Vol. 2A 3-583. It is only spec'd for r/m8 and r/m16.
There is a small chance that I'm misinterpreting that but then so is NASM which disallows this.
Somebody's wrong and so I'd like an official ruling.