Seeing now the full itinerary, Looks like they're not being on the cruise on Shabbat.
It sounds like they will be to me.
"We will visit famous castles, old Shuls, and memorials. We will make our way back to the cruise for a lavish Toamehu, and get ready for an unforgettable Shabbos experience.
Shabbos Night:
Enjoy the heartfelt Davening, led by a renowned Chazan and choir.
Delectable meals will be served, catered to perfection. Singing and dancing will take place, completing the Shabbos experience.
Shabbos:
A delicious Milchig breakfast will be served, and followed by a Kiddush ע"פ נוסח ר' ישעיה ב"ר משה.
We will then enjoy another fantastic meal.
Afterwards, we will take a relaxing walk in the Jewish Quarters, and visit the Shoes on the Danube Bank Monument.
After a musical Havdala, a hearty Melave Malka will be served."