Many premium WordPress plugins are switching to subscription models that link to publishers’ sites for verification. The ACF Pro plugin you downloaded from here is up to date and an exact match of source code, but it will not interact with http://www.advancedcustomfields.com for license verification. You could probably just tweak the plugin a bit to remove the license key popups. If there are features that require it to be connected to the publisher’s site – then you are basically out of luck.
This repository contains the latest source code for many paid plugins but no license keys. You can buy a yearly subscription from the ACF website itself if you want a license key.
Hope that helps