I don't think it is required. I think yobit will check everything post count, payment, etc. The campaign manager will check either participant creating a quality post or not. If they can create a quality post then the manager won't do anything if they fail to create a quality post then the manager will remove from the campaign.
And for payment, few projects already here on bitcointalk who are paying more than yobit so I don't think payment rate should be lower.