If the payment is too good to be true, then it probably is. Also, be sure to ask for escrow if the campaign manager isn't trusted.
No, this is not correct. there are/were lots of campaigns working which pay high pay rates per post but they are/were trusted too..
the only signs of Trusted signature campaigns I Know is:
1: The site/owner should be very trusted, old and reputable on the market.
2: if the site is new one and have no trust here then escrow is the only way to make this campaign secure and trusted.
without escrow never join any campaign, or join but be ready to get scammed.