Is it permissible to repay a debt owed to a guarantor from a project established by the debtor, and will his repentance be accepted if he is unable to repay the amount or dies, yet intended to repay it?

If a friend takes money unjustly, he is not permitted to invest it and must return it to its owner. If the amount is unknown, he should make an effort to estimate it. If he invests it and a profit is made, there is a difference of opinion among scholars as to who is entitled to it. The one who took the money unjustly must repent and return what he took. If he is unable to do so, the debt remains his responsibility. If he dies, his affair is with Allah. His good deeds may be taken from him, or the sins of the wronged person may be placed upon him, as the Prophet, peace and blessings be upon him, said: "Whoever has wronged his brother concerning his honor or anything else, let him seek his forgiveness today before there are no dinars and no dirhams. If he has good deeds, they will be taken from him commensurate with his wrong. And if he has no good deeds, then some of the sins of his companion will be taken and placed upon him."