If someone is blocking you with a prop or pushing you over a place such as the pitfall trap on Motel while the pit isn't open, it should be KOSable because if the pit were to be opened while you are being blocked over it you are 100% dead.
If you are in immediate danger, you can kill the blocker(s) The pit is immediate danger as it can be activated at any point
When the pit is open: If they are just standing still themselves or the prop it means you can't kos, however if you see them move to try and block someone then its traitorous when pit is closed: if you were standing on the pit and being blocked then it should be traitorous.
If you are being blocked from exiting a dangerous area like a trap or an incendiary, you can kill the blocker. However on the pit in motel there are two wide exits away from it so I'm not sure how one player could actively block you onto that area.