The instructions and video don’t match completely. Based on the instructions:
Data must be retrieved using REST Console. The table you need to work with is called CountryLanguage. You must retrieve data by requesting the server to return only the Language and Percentage properties. Data must be sorted by the Percentage column.
I found a problem, it was introduced in the last release. Sorry for the inconvenience, this will be fixed within half an hour and you can continue completing the missions. I will additionally inform you here as soon as the fix is released.
Thanks for reporting the issue!