Since you've got it all figured out, the following won't be of value to you so I'll post it for the benefit of those of us who haven't attained Jedi status:
If one declines Citibank's initial retention offer of 3,000 miles, they almost always will increase it to 5,000 miles. They did with me and all I did to get was to say no. This has also happened to others and a colleague actually received 7,000 miles (we think) because he had quite a large monthly spend on his account.