What is the ruling on receiving an end-of-service bonus through bribery and forging a certificate of subscription payments after the syndicate refused to disburse it due to non-payment of subscriptions along with compounded interest during the period of unemployment, knowing that the amount paid in bribery cannot be returned, and is it permissible to donate some of the amount taken through bribery while the remainder is considered against the deducted subscriptions?

We do not know the details of the conditions for obtaining the bonus or the system of union membership. However, if joining and benefiting is done in a Sharia-compliant manner, then the conditions must be adhered to, and deception is not permissible. But if it is done in a Sharia-non-compliant manner (such as usury or gharar), then it is permissible to take only the amount of paid subscriptions without any increase. Therefore, the questioner must return the full amount or whatever exceeded his installments. If returning it is not possible, he should donate it to the poor or use it for public benefits of the entity, while seeking forgiveness and repenting from paying the bribe.