Setting Up Sharepoint Apps On Premises Sharepoint 2016

I already followed all steps from this url:

https://technet.microsoft.com/en-us/library/fp161236.aspx

And I can install already APPS, and the ICON is shown fine on the site contents page.

However when I clic on it; i get a 404 error

http://app-7a42bbc34f04f4.myappsdomain.com/YoutubeFeedsApp/_layouts/15/authenticate.aspx?Source=http%3A%2F%2Fapp-7a42bbc34f04f4%2Evirtualuco%2Ecom%2FYoutubeFeedsApp%2FPages%2FDefault%2Easpx%3FSPHostUrl%3Dhttp%253A%252F%252Fwww%252Euco%252Eedu%252Eco%26SPLanguage%3Des%252DES%26SPClientTag%3D16%26SPProductNumber%3D16%252E0%252E4327%252E1000%26SPAppWebUrl%3Dhttp%253A%252F%252Fapp%252D7a42bbc34f04f4%252Evirtualuco%252Ecom%252FYoutubeFeedsApp

The Forward loookup zone and the wildcard cname is already done.

1. Do I need to make any manual step in IIS?, what about if I have 2 Front Ends with load balancer?

Thank you