Here's how you can run All in One Security WP & Firewall on your WP Dashboard while managing the WP site via InfiniteWP without getting the 302 Error.

1.) On the WordPress dashboard:

WP Security > User Login > Force Logout

Enable Force WP User Logout: Not checked, because it logs out InfiniteWP user

2.) On the Infinite WP Dashboard > Site Details > Advanced

Content Type: text/plain

Connect Using : Site URL