GSmith,
I think I found an error. The signature lines for Anguema AP in the game you see when you scroll through the list, don't match what she actually has in game.
Here is what the signature file lines look like, when you find it scrolling through the list:
https://i.imgur.com/IHLWD6r.png
And if you let the sonar shack classify the vessel as anguema, then click the ship on the map, the lines look like this:
https://i.imgur.com/82dXJGH.png
EDIT: I found civ_vtr_amguema_sig in another mod whose lines seemed to match.