Wait 5 seconds before download button appear
The only secure way would be to put the logic on the server that checks the time. Make an Ajax call to the server. If the time is under 5 seconds, do not return the HTML, if it is greater than , than return the html to show. 
Other option is to have the link point to your server and if the time is less than five seconds it redirects them to a different page. If it is greater than 5, it will redirect them to the correct content.  
Either way, it requires you to keep track of session time on the server and remove it from the client.
I know how to do that with javascript but I need a secure way to do it.
Anybody can view page source, get the link and do not wait 5 seconds.
Is there any solution? I'm working with javascript and django.
Thanks!