*Note Vodoun was the Religion of Haiti during the Haitian Revolution
The nose wipe gesture for blood actually predates the Blood Gang which was formed in 1971 by Raymond Washington - Kennedy was assassinated in 1963 which proves the society's use of the nose wipe gesture describes a different type of Blood.
"He is shot" You can see the man, issuing the nose wipe gesture behind the obstruction. - Indicating "blood"
Then the index finger down gesture is issued after indicating "blood down".
An example of the nose wipe gesture being used by Sergeant Horvath to identify Captain Miller as a blood.
Private Jackson displaying the "Wings up" gesture of the Northern Jurisdiction - Indicating that wings up can be used to fight nazis.
From the 1995 movie Panther - I believe the man issuing index finger up is displaying a modified down with the bloods gesture. Potentially index finger up represents blood in the society terms.
In the next frame he has moved his hand into the index finger down position of "down with the bloods" indicating he is actually against the community work.
This corresponds with my experience of seeing people issuing index finger down when I am doing SFN work who say negative things about the work.
I believe index finger up is the correct gesture to use for people working to improve the community.