Hello . Congrats on securing this rank and getting an option of EEE is also good.

That's a total risk of waiting till last round for CSE. But definitely you have an option yo freeze or the best opinion I can give is complete your first year and then apply for branch change. Maintain a good academic record throughout the first year.

This way you will get your campus as well as your branch . Confirm it with the college.

Hope that helps!