Is it permissible for me to donate sums of money that are financial dues owed to individuals whom I fear will harm me if I return the money to them, intending thereby to discharge myself of these obligations, knowing that I can reach them, but I am certain that they want to involve me in their evil deeds rather than reclaim their rights?

The thief must return the stolen goods to their owners or seek their forgiveness and pardon. Giving charity on behalf of the owners of these rights is not sufficient unless one is unable to reach them, and this does not absolve one's responsibility. The thief's feeling that the rightful owners wish to harm him does not excuse him from delivering their rights to them. The rights of people are not waived by such interpretations.