Defensor,
Northwestern’s BME is ranked #9 in the latest USN ranking. Also, GATech has a huge engineering population while Northwestern has smaller student to faculty ratio, which translates to more research opportunities available per student.
There are also other academic programs such as double majoring in Econ or managerial analytics certificate (through Kellogg school of management) that are available at NU (if, say, he wants to become a management consultant with focus in biotech industry).
So Northwestern can still be a better choice even if the cost is the same when you take all those into consideration, especially given that it’s not a huge difference between #9 and #3.