There was no "dual engine failure", so no RAT deployment and no loss of hydraulic power which explains why they managed to recover from the roll upset.
Also, the aircraft is still parked in a remote area of the airport according to someone that as seen it and he says that externally you cannot see any damages to the aircraft.
Bombardier's advisory wire...
Bombardier issued the following Advisory wire this afternoon concerning this incident...
"This Advisory Wire (AW) is to provide clarification on recent media reporting of a temporary loss of control
event which occurred on a Challenger 604 on January 7th, 2017.
It was reported to Bombardier that a Challenger 604 was flying over the Arabian Sea at 34,000 feet when it
experienced a temporary loss of control which resulted in significant loss of altitude, abnormal flight attitudes,
and accelerations beyond the certificated flight envelope.
Shortly after the event, the crew shut down one engine due to a high ITT (Inter Turbine Temperature)
indication; the other engine remained operational. The crew eventually regained control of the aircraft, later on
relit the engine which had been shut down, diverted from their intended destination and landed safely without
further incident. There were serious injuries to some passengers on-board. The flight crew reported that shortly
before the event an oncoming large transport category aircraft passed them with 1,000 feet clearance above,
and slightly offset to the left.
The German Federal Bureau of Aircraft Accident Investigation (BFU), representing the State of Registry of the
Challenger 604 involved in this event, has classified the event as an Accident and initiated an investigation
pursuant to ICAO Annex 13 protocols. The Transportation Safety Board of Canada (TSB), representing the
State of Design and Manufacture of the Challenger 604 has been appointed as an Accredited Representative
to the investigation. Bombardier has been appointed as a Technical Advisor to the TSB for the purposes of this
Note that Bombardier cannot provide further comment on the investigation beyond what has been stated in this
AW. The BFU, as the investigating agency, will communicate investigation progress as and when it deems fit."