As everyone said above - UA liability is limited to the E+ seats you paid for - nothing else
Will they give you a goodwill gesture - maybe

As far as travel - this happened to my parents this winter, your FIRST call should have been to the travel agency, they are the one responsible to get you from point a to point b and on the ship. They can buy you different tickets, re route you, all kinds of stuff. UA is limited by what it can and will do, your TA is NOT.

My parents sail on Regent and their contract is clear that in case of any issues call this number and if they don't any expenses incurred are their own, so if they decided to stay home, they would lose everything they paid as the travel agent didn't tell them to stay home.