As noted in the quoted material, I started this thread back in April concerning the possibility of Oceania offering Venice shore excursions while Marina is docked in Trieste. I have been checking daily since April waiting to see if such excursions might eventually be offered.
A couple weeks ago it occurred to me that since we were taking an 18 day cruise (November 1 through 19) composed of several segments I should check smaller segments. Lo and behold I found that Venice excursions WERE offered on the November 1 through 11 Marina segment which (obviously) was scheduled for Trieste the same day we were. I called Oceania to ask if I could book one of those tours and was told that this was not possible until the tours were loaded onto the November 1 through 19 itinerary. They promised that the shore excursions office would be asked to do this. I continued checking and (to make a long story shorter) called three more times, weekly, with similar unsuccessful results. Finally, however, the Venice tours were added for our November 1 through 19 booking today, June 24.
I mention all of this to (1) let anyone else on the itinerary know of this availability, and (2) to let everyone know that the glitch that led to our experience could be a recurring one -- so be forewarned in the context of other bookings.