The October surprise that Donald Trump has been talking about seems to be divorce papers that Michelle Obama had intended to follow through on to divorce Barack Obama. It has long been a rumor, which the Obama family has denied, that Michelle intended on leaving the president in 2000 after he risked their “stable and secure future" on a risky House seat election which he lost. Trump now has these papers in hand and will be releasing them tomorrow.
I'm sure it will be interesting to a lot of people to read but Trump said this would shock everyone and change the course of the election. I don't see how papers that were prepared 12 years ago for a divorce that never happened will change much.