This information should be found attached to the email labeled:
Important – Viking Final E-Document
There is a pdf attached titled Your Final Travel Document
This contains all the information about ship location, phone numbers, email address, emergency contact info, etc. For extensions it also contains hotel information.
You’re not the first person to ask about this. Viking tends to send a lot of emails but this is THE most important one. I always download a copy of it local to my phone in case of emergencies.