I'm also seeing this with the message `hook failed: "grafana-dashboard-relation-changed"`, in testrun https://solutions.qa.canonical.com/testruns/testRun/9e2d7f5d-7076-43f0-a522-b44ef20c5d37.

The messages in the logs look the same:
```
2022-07-01 16:43:10 ERROR unit.ceph-dashboard/2.juju-log server.go:319 grafana-dashboard:92: Command failed: b"Error EIO: Module 'dashboard' has experienced an error and cannot handle commands: [('x509 certificate routines', 'X509_check_private_key', 'key values mismatch')]\n"
Traceback (most recent call last):
  File "./src/charm.py", line 379, in _run_cmd
    output = subprocess.check_output(cmd, stderr=subprocess.STDOUT)
  File "/usr/lib/python3.8/subprocess.py", line 415, in check_output
    return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
  File "/usr/lib/python3.8/subprocess.py", line 516, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['ceph', 'dashboard', 'motd', 'clear']' returned non-zero exit status 5.
```

and
```
2022-07-01 16:43:11 ERROR unit.ceph-dashboard/2.juju-log server.go:319 grafana-dashboard:92: Uncaught exception while in charm code:
Traceback (most recent call last):
  File "./src/charm.py", line 645, in <module>
    main(get_charm_class_for_release())
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/main.py", line 431, in main
    _emit_charm_event(charm, dispatcher.event_name)
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/main.py", line 142, in _emit_charm_event
    event_to_emit.emit(*args, **kwargs)
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/framework.py", line 283, in emit
    framework._emit(event)
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/framework.py", line 743, in _emit
    self._reemit(event_path)
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/framework.py", line 790, in _reemit
    custom_handler(event)
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/src/interface_grafana_dashboard.py", line 41, in _on_relation_changed
    self.on.dash_ready.emit()
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/framework.py", line 283, in emit
    framework._emit(event)
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/framework.py", line 743, in _emit
    self._reemit(event_path)
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/ops/framework.py", line 790, in _reemit
    custom_handler(event)
  File "./src/charm.py", line 428, in _configure_dashboard
    self._configure_tls()
  File "./src/charm.py", line 552, in _configure_tls
    ceph_utils.dashboard_set_ssl_certificate(
  File "/var/lib/juju/agents/unit-ceph-dashboard-2/charm/venv/charms_ceph/utils.py", line 3569, in _dashboard_set_ssl_artifact
    subprocess.check_call(cmd)
  File "/usr/lib/python3.8/subprocess.py", line 364, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['ceph', 'dashboard', 'set-ssl-certificate', 'juju-a8584f-1-lxd-1', '-i', PosixPath('/etc/ceph/ceph-dashboard.crt')]' returned non-zero exit status 5.
```

The crashdumps for this testrun can be found here:
https://oil-jenkins.canonical.com/artifacts/9e2d7f5d-7076-43f0-a522-b44ef20c5d37/index.html