Is it permissible for a married couple to perform Umrah despite having debts and outstanding checks owed to many parties from whom it is impossible to obtain permission, seeking to avert harm and draw closer to Allah given their difficult circumstances?

If the debts are deferred, there is no harm in traveling for Umrah without the creditors' permission. However, if they are due, it is not permissible to travel without their permission, and they have the right to prevent the debtor from traveling, unless the debtor is in straitened circumstances (insolvent), in which case permission is not required and the creditors do not have the right to prevent him.