Am I being selfish on not waiting to put down my dog?

I am in the military stationed in the US and my dog with lung cancer (she is 13) is with my family in Europe. I have been told the vet suggested they euthanize her but my mother is heartbroken and doesn’t want to.

I am planning to visit 27th of Nov to see her before she passes away. Is this too long to wait for my dog? She has bladder problems, has less interest in food and activity. I have been reading articles that say these symptoms are signs that she should be euthanized… when she doesn’t “act like a dog” anymore.

I am pained and not sure what to do. I want to be there but weeks feels too long. I don’t want her to die at her lowest point.