I think it was fixed in an earlier version of Build 14 that Tortuga would be Pirate and always accept Pirate Flags in Jack Sparrow.
There does not appear to be a problem with Tortuga - I have just tried twice sailing there directly after meeting Davy Jones - sailed in and moored with no problems both times on sunny days with very good visability.
Just played this bit again - Arrived in Tortuga safely - decided to go and loot the chests on my ship - while doing this on the gun deck I got the on -screen log message " We are recognised, captain"
Went to the port and saved on the jetty.
In the compile log
Code:
FLAGS: The 'La Tortue Fort' has recognized our false Pirate flag at range=120.99 with visibility=555., chance=5.3417e-002 and frnd=3.5127e-002
FLAGS: The 'La Tortue Fort' turned hostile as they have recognized us
It will be interesting to see what happens when I sail out of port with Barbossa - Pintel & Ragetti.
EDIT :- This is with the 22nd Sept version of the game. ( most recent changes not included )