Tees, further to the OEI question - yes, the 139 is capable of being OEI at less than 50kts or in the hover, but you can only assess that by reference to the PI and your drop down height (if you have remembered to Perf Init the FMS).
No mention of either in the video clip, especially in the critical stages of the approach.
The 50 kts figure in the QRH is clearly a one-size fits all figure valid for the whole of the flight envelope - it also mentions acceptable rate of climb and safe clearance from the surface.