I just went through this exercise and it took me a while to find the mistake. There is an error on the .docx attached for the above mentioned article.
https://support.ruckuswireless.com/articles/000006316
Specifically, steps 7. On this step a reference to creating a JSON file called role-policy.json where the unix/linux command to create it calls it role-policy-json and the awscli command to apply it is also looking for role-policy.json, you will get an error.
