Fake news investigator is for sure good idea and it is required. Community voting is not the right way to determine if something is false or not.
Every form of voting is subject to manipulation. I am not sure how you think to prevent paid voting or using telegram bots farming. Plus, for example, by voting directly depend from where I am informed, did I'm read real or fake content and how it's affected my opinion.
Fake news and feedbacks It's all around us, simple check bounty section here on the forum, you will see many "paid" action, even claps on Medium.
It is better to gather a group of people who will research and post analytics about some news and explain if they found the news to be fake.