No I hadn’t heard of it. Apparently its sovereignty wasn’t respected.
Ronaldus Magnus was wise enough to realize that we were at war (Cold War) and that the intelligence that could be gathered was worth the risk of breaking international law.
The reclusive Howard Hughes was nearly incapacitated with his germ phobia at the time. But was still a patriot enough that he met personally with the CIA officials who wanted his cooperation in the project to recover the sub.
Truly an amazing but true story. Sad that we don’t have more successes like that.