I believe the Greeneville was executing an emergency surfacing maneuver when it struck the Japanese ship.
Yep...Greeneville had some VIPs on board...CO wanted to show off and performed an emergency blow to surface without doing a full 360 visual check of the surface before going deep to prep for the maneuver.
Million to one odds that he would surface right under the Japanese boat...but if he would have done his job properly, the incident wouldn’t have happened.