Он, должно быть, не сумел передать

Он, должно быть, не сумел передать им нашу записку, и они, возможно, ждут нас.

Результаты (английский) 1:

He must have failed to convey to them our note, and they might be waiting for us.

Результаты (английский) 2:

He must have failed to convey to them our note, and they may await us.

Результаты (английский) 3:

he shouldn't have been able to give them our note, and they may be waiting for us.