Can we update an object through the REST API without using t

Is there a way to get the REST API update method to allow object updates with a key that is not a Rollbase ID for that specific object update. For example occasionally we want to specify the object to update based on a key that isn't the Rollbase ID (and sometimes the script on our end simply doesn't have the Rollbase ID). Also occasionally we have objects that use the same referenced field between each other as a key.