That is odd. I would suggest contacting Amazon Alexa support. There is nothing on our side we can really do to troubleshoot multiple camera skills and why Alexa would have problems … as long as the device names are different across the multiple camera skills (which in your case they are “Front Door” (Ring) and “Nursery” (Monocle) ).
The Monocle skill is a “smart home skill” and thus all of the voice commands are entirely managed by Amazon. So it’s not like we are getting the request and can’t figure out which camera to provide. We only receive request from Amazon with the targeted camera that Alexa has pre-determined.
Sorry, v0.0.5 has been on hold while I tackle other commitments. So not much recent progress there.
You could just create a docker volume for holding the config file (monocle.token, monocle.properties from /etc/monocle) so that the container is not mounting any writable path on your host, but the docker volume could persist your monocle config outside of the lifecycle of the container instances.
In the interim … if there is anything you can do to the docker image to make the config better/easier, feel free to make changes to the Dockerfile and submit a pull request and I can include it in the image: https://github.com/MonocleCam/monocle-gateway-docker