I just watched this. Wow. So Janeway breaks the rules for the people: specifically, Tuvok and Seven. She doesn't want Seven to die (apparently a boring death on an away mission; nothing spectacular like the Queen stabbing her or something). She also doesn't want Tuvok to suffer the neurological disease.
So is it in Janeway's character to break the TPD to help Tuvok and Seven in major ways, and get her crew home in 7 years?
Is it in Janeway's character to just break her word with that Klingon and just steal the time thingy?
If we all were given the ability to time travel if it meant saving someone(s) we were very, very close too, who wouldn't? What do rules matter in dealing with affairs of the heart? It's in ALL our character to do so.
She wasn't given the ability to time travel; she had to steal it. But I think it is within her character and personality to do that. She was going to make a better life for Tuvok, and a life for Seven.