The key issue here is the missleading event description, that still is "Complete Event Objectives to earn Anniversary Coins and get rewards" after the event allready ended.

Like you can see from this thread, I'm not the only player that didn't recognize that. 

Especially problematic is the difference to tournaments that are allready over. They are not highlighted anymore, but you can still claim rewards when you click on them until they disappear. Galek's path is still highlighted and has a description as if it would be still active.

I was offered to buy some event points even after the event had ended....