Он, должно быть, перепутал ключи и

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

Результаты (английский) 1:

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

Результаты (английский) 2:

He must have confused the keys and took the key instead of his neighbor.

Результаты (английский) 3:

He must be confused keys and took the key neighbor instead of its own.