Have the deceased's brothers and relatives committed a sin by moving his body contrary to his written will, and what must they do now, and are they obligated to give sadaqah for not following the will?

Executing the will of the deceased is obligatory. The deceased should not be moved from his town to another except for a valid reason, such as protecting the grave from desecration or transporting the deceased to his homeland to please his family, provided there is no fear of alteration or violation of his sanctity. The fundamental principle is that the deceased should be buried in the cemeteries of the town where he died. If there is no necessity or if the conditions are not met, then it is not permissible to transport him. If the relatives violate the will unintentionally, there is no sin upon them. However, if they intentionally violate it, they are sinful. Likewise, transporting the deceased a distance without a valid reason is considered an infringement upon his right. They must repent, seek forgiveness, and supplicate for the deceased.