Possibly. There's also the option that he shot himself after going to Vorobyov.
1. He shot at the monkey.
2. He shot at Vorobyov and hit Mental.
3. He shot at Vorobyov and hit himself.
Added after 45 seconds
No, 4: He shot at Vorobyov and hit the monkey.
Если где-то чего-то убудет, то в другом месте добавится.
(Закон сохранения).