I found this:
Quoting J&E:" I couldn't find light corn syrup. We might call it something different here. We bought packet royal icing. It says egg white powder :/"
One of the reviews said this:
If light corn syrup is not available, you can substitute a sugar syrup made with 1-1/4 cups sugar and 1/3 cup water, boiled together until syrupy.
I've made royal icing with 'no-egg' powder. Was just as good :D