Zoro was fully recovered the moment Ryokugyu took on King and Queen. Now Zoro took Hakai times two, since the medicine doubles the previously received damage, while King has ancient Zoan recovery.
If King wasn't fully recovered while Zoro was, it means that either Zoro's endurance and recovery rate is magnitudes above King and Queen, or that Zoro's attack power is beyond Hakai times two.
Which one do you choose?