Often these sorts of inconsistent decision making occur because multiple people making decisions disagree. Maybe some person high up in HR in change of recruiting scheduling decided Duke and A&T would be visited on these days. Maybe the person in charge of planning the details felt very strongly they were better off putting whatever resources earmarked for A&T toward events with minority-focused engineering student groups at Duke, and so raided the budget without going head-to-head with the person in charge of recruiting scheduling.