I can't see the still image from the movie but, yes, London Ambulance Service uniform is a fairly dark green. The green has been through various shades over the last twenty odd years but was chosen to be specifically different to the dark blue of the police. The current pattern of operational uniform was introduced around 2002 (with minor tweaks since) and is now pretty much the national pattern for NHS ambulance services.
This is outgoing chief executive of the LAS, Dr Fionna Moore, in the female variant of the LAS formal uniform, attending a memorial service for the victims of the "7/7" terrorist attacks in London (July 7, 2005), alongside the Commissioner for the London Fire Brigade (a title unique to London, but he wears the same Chief Fire Officer insignia as all other CFOs). This is, presumably, the real role that the movie was attempting to create...?
The markings on LAS green uniforms are gold rather than the silver worn on the dark blue (not black!) uniforms of the police and fire services. The only exception to this would be the City of London Police, who wear gold insignia on dark blue uniforms.
From the same event:
From left to right:
Left: City of London Police: note the gold insignia and gorget/cap oak leaves and also the red-and-white diced hat band (reflecting the red and white colours of the Arms of the City of London) rather than the usual black-and-white diced pattern.
Centre: Metropolitan Police (Commissioner Sir Bernard Hogan-Howe)
Right: British Transport Police (I think...)