Jake recovered in 2 days after resting up at Grey's Base. During these 2 days, he heard a lot of commotion in the base because of the continuous movement of people.
Martin, "It is good that you have recovered so fast because of the potions and your own body's capability. Many people would have taken up at least 10-15 days to recover from those injuries. Meanwhile, there is good news for you, it seems because of the information you provided us last time, we got some clues about the previous incident. Many people thought it was only done by Blackheart but it seems there were many people involved in it. you can leave any time as you have recovered already. Master Vlad might already be waiting for you at North-frontier town."