I don't think that LEX is an up-down facility (and even Marion didn't say the second controller would have been in the base of the tower). A lot of smaller towers have their radar in the cab. I've read in various accounts that the controller on duty was responsible for radar as well as ground, which would indicate the radar at LEX is in the cab.

It's certainly in Marion's self interest to say that staffing the tower to policy wouldn't have changed things. This is also a woman who was caught in a lie (said it was an "oral guidance" to have the tower staffed with a min of two when there's a written memo from Nov. 2005 saying it's a requirement) and who kept saying the accident took place in Louisville.