Glad to hear that worked for you.
I don’t know if the gnome people can make this very much easier. Different version of different linux distros might invoke hibernate differently. How would they know which one to map to the lid button?
Also, some people might want to invoke sleep rather than hibernate. If there were system commands which were persistent over all distros and versions, then maybe they could offer these two mention options (with explanations of each). Yes, that would be an improvement.