Assigning the same FontIconText string in C# doesn't work the same as in Xaml. The rendered menu just displayes the "i" as the option not the icon text.
Previously I had creates the items collection for the Radial Menu in Xaml and that worked fine:
<radialMenu:SfRadialMenuItem ItemTapped="OnSaveRadialMenuItemTapped" FontIconText="i" IconFontFamily="{StaticResource customfontfamily}"></radialMenu:SfRadialMenuItem>
c# (doesn't render the icon):
var item = new SfRadialMenuItem() {
FontIconText = "i",
IconFontFamily = Device.RuntimePlatform == Device.Android ? "Edsembli" : "Edsembli.ttf";,
};