Camo painted M16-18 are tough, as they were mostly battle worn helmets, then painted in the field, after 7 July 1918.
A good sign though, is look at the photo of the reverse. The missing liner brad pin is clearly been painted around. So that brad was on the helmet when it was painted. A clear impression is left of the pin. So that's good.
The color without patina and the fact that in the second photo the crack on the front has a stroke where the color is not separated and then continues in the crack leaves me some doubts about the authenticity of the camo and sets off some alarm bells.
It would be necessary to see it in your own hands to have certainties.