Samantha, you are responsible for the chair, and expected to keep it in your room when you are in your room.
Cast Members can - and will - move the chair if they believe it to be causing an obstruction of traffic, or a potential traffic issue. (This is true of anywhere on property - just like they are often moved at the Theme Parks for traffic purposes.)
Additionally, you might want to price out the replacement cost for that chair before you leave it unattended overnight - if it is stolen, or "misplaced" you may be on the hook to the rental company for full replacement cost; check the fine print in your rental agreement.
Just because your Godfather doesn't want the chair in your room doesn't mean you are allowed to park it in the hallways. This issue has been discussed here before.
It's about creating a potential obstruction in a hallway that could impact other Guests.
It's about leaving a high-ticket item unattended in a public space.
It's about leaving an item that requires a full overnight charge (by being connected to a power outlet) in order to function fully and effectively the next day.
It's about leaving the very piece of equipment that you are relying upon to be your legs at WDW out of your control all night long. What if someone comes along in the middle of the night, and unplugs it? You will spend the next day constantly searching for outlets in the Parks instead of having fun. That, BTW is the best case scenario. They could also move it - down the hall, or to another floor or building, or even push it into the pool. They could hide it in a Guest room, and until the Resort was searched, room-by-room, no one would know where it was.
Yes, WDW *is* a safe place - the vast majority of Guests there never have a problem with the security of our personal items. But that doesn't mean that it can't happen... and leaving an item like a power chair unattended all night in a public hallway could pose an opportunity for mischief that needn't have happened.
It's about being an adult, and taking responsibility for this piece of equipment. Yes, we all come to WDW to live inside the "bubble" for a few days, and escape reality, but that does not mean that we can just ignore our basic adult responsibilities.
Sometimes, doing what is right takes a bit more time or trouble than what is easy. Please do the right thing, every time. We have enough folks in the world who try to take the easy way out.