His copilot on that Gemini mission, David Scott also praised Armstrong's actions. In the book Two Sides of the Moon he wrote something to the tune of "I don't know how Neil did it, but he did it", but I think it was related to pushing some buttons in an awkward place in an overhead panel in the spinning spacecraft with little time left.

I think that's closest there can be to an original source for that event. Scott was there.