Hi there!
Sno has the right idea - you need to make sure that you don't use anything else when you're going to for camo unlock Bloodthirsties.
That means no recon stuff in the air, no stuns, no other players helping out.
I think the confusion with this is that there's really two types of bloodthirsty medals; ones you get for 5 kills without dying, no single weapon needed, and then there's the ones unassisted that you need for camo unlocks.
Both will pop up ingame as medals, but only the unassisted ones will count towards the camo unlock.
And Sno, thanks for the great answer and the help. 
^LM
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