public class RecordWrapperClass {
    @Auraenabled public  List<SObject> objectRecordList1 {get; set;}
    @Auraenabled public  List<Schema.FieldSetMember> fieldSetMemberList1 {get; set;}
    @Auraenabled public  Map<Id,String> subjectOfAllegationsMap1 {get; set;}
    @Auraenabled public  Map<Id,String> personAllegedlyImpactedMap1 {get; set;}

}

@wire(fetchAllegationDetails, { parentIdToPass: '$recordId', tabnameToPass: 'Allegations', objectNameToPass: 'Allegations__c' })
fetchAllegationDetails(result) {
    if (result.data) {
        console.log('=====> this.refreshData ' + JSON.stringify(result.data.length));
        this.recordSize = result.data.length;
        this.allegationRec = result.data;
    } else if (result.error) {
        console.log('=====> result.error ' + JSON.stringify(result.error));
    }
}

=====> result.error {"ok":false,"status":400,"statusText":"Bad Request","body":{}}