Simon-pierre,
I don't think that you need to translate Filé Gumbo, it's the name of a Cajun dish.
To 'pole' is to move the boat by pushing against a pole that you put in the water, it is long enough to reach the bottom. In England they have flat bottomed boats called punts which they pole along the rivers.
machez a mio - I've always assumed that this was a corruption of 'ma cher ami'
'Go hog wild' - make a lot of noise - party wildly. The houses near the water are built on stilts. My second wife, Lou, who came from down that way, said she has seen them shaking with the noise and dancing at a party.
Yes 'by the dozen' means 'crowd'

Sorcha, just to be real pedantic, Gumbo is made using filé OR okra. NEVER both (not the real stuff anyway)

Bert.