The engineer from the Skyraider said after the incident that the pilot still had lateral control; amazingly two of the three aileron hinges were still intact(ish) and the aileron itself was all there, albeit a bit bent; so I guess the roll was just the remains of the energy from the manoevre.
The aircraft's still in our hangar awaiting a replacement outer wing so it can go home. We too await the report with interest; shouldn't be long, what with all the evidence and two survivors to interview. Hats off to Rob, even our own pilots could scarcely believe that it was a survivable escape.