Он, должно быть, перепутал ключи и

Он, должно быть, перепутал ключи и он взял ключ соседа вместо своего.

Результаты (английский) 1:

He must have mixed up the keys and he took the key instead of its neighbor.

Результаты (английский) 2:

He must have confused the keys and he took his neighbor's key instead.

Результаты (английский) 3:

he must have got the keys, and he took the key from its neighbor.