Survey Junkie anonymizes all the data they collect, and your name is never attached to any of it. Credit card numbers, email addresses, passwords, and usernames are not collected or saved in any way. So, yes, it’s safe to use Survey Junkie.
Unfortunately, Cash App is not listed as a payment option on Survey Junkie’s platform. Currently, the only supported payment methods are PayPal cash and gift cards from popular brands like Amazon and Target.