Gentlemen,
I suspect you have uncovered the lair of a legendary creature, never before sighted.
The ultra secret GHG passive sonar system, deploying 60 hydrophones per side. A seperate bulge/fitting like this on the outside of the ship, allows 60 penetrations without threatening hull integrity, just one multicore takes the wiring inboard. The bulge can have acoustic deadening material to isolate the hydrophones from hull borne noise, motors, stomping jackboots, other machinery, clicking heels etc and if there are problems, the whole fitting can be removed. etc.
The Prinz Eugen system was removed by the US authorities and redeployed on the submarine USS Flying Fish as a test bed and rumoured to be the progenitor of USN passive sonars post war.
Many lengthy threads have discussed whether this system detected Hood and PoW at over the horizon ranges (which we can't really do now from a noisy surface ship) and permitted PG to dodge every single torpedo fired at her except the one that hit and blew her stern off.
If there are any more pictures we might see the beast properly.
Anybody agree
All the best
wadinga