Just posting the fix for the above as I figured it out.
The content attribute for the css is incorrect. On IcoMoon site, hit “<> Get Code” under the icon. Then copy this to ionic.app.css or style.css.
.ion-wink:before {
content: "\e9e8";
font-family: "teaze";
}
Works a charm and easy way to add icon fonts to your app without messing around with the ionicon library