Can only start local clusters and not with SLURM

We are currently trying to run dask, jobqueue and labextension on our cluster as a test. We could start a cluster by hand and also with the jobqueue file.
We cannot start SLURM Cluster with the dask-labextension. It is probably simular issue with this one https://github.com/dask/dask-labextension/issues/68 or it is just a miss configuration.
We could start the cluster by hand without troubles. When we use the dask-labextension we got the following error:

> Cluster Start Error
> 'LocalCluster' object has no attribute 'scheduler'

It looks like he's trying to start a local cluster, but we've adjusted all labextensions.yaml files we could find.
~/.config/dask/
we copied also to /etc/dask
and also in the /usr/local/lib/python3.6/dist-packages/dask_labextension folder.

Does someone have an idea what I'm doing wrong?

labextension:
```
labextension:
factory:
module: 'dask_jobqueue'
class: 'SLURMCluster'
args: []
kwargs: {'cores': 1,
'processes': 1,
'memory': '40GB',
'interface' : 'ib0',
'queue': 'gpu',
'walltime': '0:30:00',
'project': 'gpu'}
default:
workers: null
adapt:
null
# minimum: 0
# maximum: 10
initial:
[]
# - name: "My Big Cluster"
# workers: 100
# - name: "Adaptive Cluster"
# adapt:
# minimum: 0
# maximum: 50
```

pip list :
```
dask (2.2.0+12.gb5722b36)
dask-jobqueue (0.6.2)
dask-labextension (1.0.3)
```

jupyter serverextension list:

```
config dir: /usr/etc/jupyter
dask_labextension enabled
- Validating...
dask_labextension 1.0.3 OK
config dir: /usr/local/etc/jupyter
dask_labextension enabled
- Validating...
dask_labextension 1.0.3 OK
ipyparallel.nbextension enabled
- Validating...
ipyparallel.nbextension OK
jupyter_server_proxy enabled
- Validating...
jupyter_server_proxy OK
jupyterlab enabled
- Validating...
jupyterlab 1.0.4 OK
```