Mohammad lend a big sum of money to Ahmad to help him in his business and told Ahmad (verbally) to return him the money .....

Question

Assalamualaikoum,

Mohammad lend a big sum of money to Ahmad to help him in his business and told Ahmad (verbally) to return him the money after 6 months. But before 6 months, Mohammad came and claim his money with Ahmad. Ahmad told him that he invested his money and he can't give him back now as the condition was after 6 months. Mohammad refused to listen and he filed a criminal case in court against Ahmad. Mohammad lied regarding the 6 months condition in court as there is no proof and he wins his case. Ahmad told the court that he don't have money to pay mohammad back as he invested it in business. The court sentenced Ahmad to 6 months of imprisonment. The case was over and mohammad left the country and went to settle in another country. Ahmad went in prison and he is out already. After a while now Ahmad want to perform Hajj. What is worrying Ahmad now is, does he have to still return Mohammad his money before going for hajj or is it paid automatically after spending time in prison?

The reason for this question is Ahmad said he heard that if a person owe another person, he will have to settle the debt before going for hajj.
Note that Mohammad left the country and no contact at all with him.