I've just run a test of the ships in question and sunk them all with ONE TOPEDO! This test was made using the GWX2.0 final beta release and GWX 1.03 production release.
As far as I can tell there is NO PROBLEM with these units in game.
As may you know GWX uses a combination of damage and flooding to sink units and hitting them in the right place (For me the bow area works everytime), and giving them enough time (<1 hour in game) These units sink with one torpedo shot.
@Gorshkov, Thanks for wasting our time.
