Yes, this can lead to breakthroughs for extending human life because experiments like this often translate into cures for humans. There are many similarities between mice and humans and by seeing what makes a mouse live longer will help us understand what might make a human live just as long.
Yes, Yoda's life will give us things we can study to extend human life. For example, scientists can evaluate Yoda's genetics. Perhaps he lived that long because he was blessed with good DNA. Alternatively, perhaps Yoda's long life was environmental. If environmental factors extended his life, maybe there are things humans can learn from that.
It's just a lab mouse. It was used for an experiment about aging so that's why they created separate housing. It's not that you can send your own rat to a geriatric home when it gets old. It's not even surprising that this rat got so old because housing/living conditions for lab mice are on average way, way, WAY better than living conditions for pet mice.
This may be a way to extend human life, but this is a seclusive life with little social interaction. Humans are a social species and even people who are strongly introverted need some social interaction. To follow the lifestyle of the mouse would be to isolate humans in pairs and disinfect the room continuously. As most people know, there would be problems that develop between the humans in the room that would force the people to want to separate, but they can't because they are forced to be in the room together.