I'd say use this new information to ask both K and D if they would be interested in revisiting their scholarship amounts.
I doubt if K will do that since they already have your deposit and now know that they almost have you.
Duke on the other hand just might give you more $$ for a couple of reasons,
1) If you throw in enough information about the scholly from K and UNC, it would be in Duke's favor to go one up on them and get you on board
2) They already want you bad...the previous offer was itself good so a few thousands more would not make much of a difference
Tell Duke that they are your top choice and how much you loved them after the BDW, but because of the UNC/K development you are having a hard time deciding....
There's no harm in trying...the deposit deadline for Duke is just a couple of weeks away so they'd now have a fair idea of the yield and also dispensible cash if any..
And yeah, stick to Kellogg or Duke...they tie in to your goals very well...
Hidden agenda here: Get Nervous to go to Duke, get's me another great classmate...if I end up there..ssssssssshhhhhhhhnervousgmat
So the matters got a little more complicated now as I found out that UNC has selected me as a Premier Fellows Program participant, the honor extended to only 6% of admitted applicants. I am super excited and ... still stuck. The allure of free education is very attractive for me.