For such topic, I would never rely on what some CX phone agent says.
You need to get direct government information. My guess is that originals might be required.

I assume that you will be traveling with your family. If not, you'd better be already in HK and provide your spouse with proof of your residency.
I don't know your (and wifey) citizenship. Remember that the documents have to be in English (or Chines), otherwise an official translation is required.
In other instances, there have been cases of fake documents, so there might be suspicion from some citizenships.