Hello,
Your brothers case has been sent to enhanced security screening. that is why they are request all these documents again.
CV is just regular cv. It should include the filed of study, period, data, supervisor, etc., and any work that the person did, place of the job, role, any publication, ..
But, I don't know what exactly grad/kit is. I think it is just for making sure that you include the details of the study in the CV. They also sometimes include some info in the email. If not, raise a CSE and ask them what to do
Let's see what other members suggest on your questions.