Yes, Rumsfeld did make this speech on the day before the attacks. It's actually a great speech too! He talks about the cumulative bureaucratic waste of the previous few years of the Department of Defense, and poor auditing.
https://www.c-span.org/video/?c4623026/donald-rumsfeld-speec...
https://www.cbsnews.com/news/the-war-on-waste/
https://www.quora.com/What-does-the-missing-3-trillion-dolla...
But the section of the Pentagon that was hit was not the "accounting wing". There is (and was) no "accounting wing". The specific areas that were hit were mostly "Naval Command Center" and "Defense Intelligence Agency", but even then, the area was relatively unoccupied due to renovations that started in 1998.
https://en.wikipedia.org/wiki/File:FirstFloor_Pentagon_Bodie...
https://media.washingtonpost.com/wp-srv/national/images/pent...
https://en.wikipedia.org/wiki/American_Airlines_Flight_77#Cr...
https://en.wikipedia.org/wiki/The_Pentagon#September_11,_200...