Child was roundly booed off the field at the end of a pulsating Super League encounter at the Wish Communications Stadium after awarding several contentious decisions in the Dragons' favour.
Millward did not openly criticise Child's performance, apparently wary he could face repercussions by speaking out, and instead invited the surrounding journalists to give their opinion on the officiating.
The Australian also added that his side may have been hard done by in the defeat against Bradford last week, with the referee from that game, Steve Ganson, handling a Championship game this weekend.
Millward said: "What about last week? Let's go back to that. The referee we had got dropped to the Championship: Keighley versus Swinton.
"What's your thoughts on that? Do you think that should be something that should be done to referees if they don't ref up to standard?"
When one journalist highlighted that is what can sometimes happen in football, Millward added: "They do that in football, exactly, sometimes they stand them down. But we can't stand too many down because we don't have a lot.
"We've got on very well in defence and created a lot of opportunities in attack but maybe we were denied some opportunities in other areas of the game."
Millward added: "I wish you didn't have to interview me men, I really do. You should be allowed the luxury of interviewing not only the coaches, but a player here now - which would be brilliant - and maybe even an official because I'm not allowed to ask questions.
"I reckon that would be great if you guys could ask some questions because I'm not allowed."