[BlueCop]

no script just search & replace in a text edioter.
search for
"2_420_manchesterunited_burnley_2014_h_whole_1_450 0_"
replace with
"http://nlds4.cdnllnwnl.lon.neulion.com/nlds_vod/coliseum/vod/2014/08/30/420/2_420_manchesterunited_burnley_2014_h_whole_1_4500 _"

I thought you said you already obtained the key. I misunderstood. If you are proxying the connection then you should be able to see the key as it is transferred. Can you save it from there?