<!--- Verify first that your issue is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
<!--- Explain the problem briefly below -->
While using a simple reproducer with either force_valid_group_names=silently or force_valid_group_names=always an unexpected exception is thrown:
Sample playbook:

```
---
- hosts: localhost
  connection: local
  gather_facts: false
  tasks: 
    - name: add a host to a group
      add_host:
        name: localhost
        groups: Not-Working
```

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
inventory
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```
ansible --version
ansible 2.9.0.dev0
  config file = /opt/gmuniz/ansible.cfg
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /opt/ansible-devel/ansible/lib/ansible
  executable location = /opt/ansible-devel/ansible/bin/ansible
  python version = 2.7.5 (default, Apr  9 2019, 14:30:50) [GCC 4.8.5 20150623 (Red Hat 4.8.5-36)]

```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```
ansible-config dump --only-changed
TRANSFORM_INVALID_GROUP_CHARS(/opt/gmuniz/ansible.cfg) = always

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
CentOs-7

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```
- hosts: localhost
  connection: local
  gather_facts: false
  tasks: 
    - name: add a host to a group
      add_host:
        name: localhost
        groups: Not-Working

```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
I expect the host to be added to the group either with the originally provided name or the replaced underscore name.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```
TASK [add a host to a group] *************************************************************************************************************************************************************************************
task path: /opt/gmuniz/add_host.yml:6
creating host via 'add_host': hostname=localhost
 [WARNING]: A duplicate localhost-like entry was found (localhost). First found localhost was localhost

 [WARNING]: Invalid characters were found in group names and automatically replaced, use -vvvv to see details

ERROR! Unexpected Exception, this is probably a bug: u'Not-Working'

```

return None
        cur_pass = 0
        while True:
            try:
                self._results_lock.acquire()
                task_result = self._results.popleft()
            except IndexError:
                break
            finally:
                self._results_lock.release()
            
            original_host = get_original_host(task_result._host)
            queue_cache_entry = (original_host.name, task_result._task)
            found_task = self._queued_task_cache.get(queue_cache_entry)['task']
            original_task = found_task.copy(exclude_parent=True, exclude_tasks=True)
            original_task._parent = found_task._parent
            original_task.from_attrs(task_result._task_fields)
            task_result._host = original_host
            task_result._task = original_task
            
            if '_ansible_retry' in task_result._result:
                self._tqm.send_callback('v2_runner_retry', task_result)
                continue
            elif '_ansible_item_result' in task_result._result:
                if task_result.is_failed() or task_result.is_unreachable():
                    self._tqm.send_callback('v2_runner_item_on_failed', task_result)
                elif task_result.is_skipped():
                    self._tqm.send_callback('v2_runner_item_on_skipped', task_result)
                else:
                    if 'diff' in task_result._result: