Probably the best way is to use monaco tool where you can have a dashboard template and create a dashboard for each device. You will have a separate dashboard for each device.
You can also have a single dashboard and use Management Zone to filter only the devices you need in the dashboard. But you would need to create MZ for each device. You can also use monaco for that.
Unfortunately, since it's a custom device, you can't use dashboard dynamic filters as there is no suitable filter.
@Larry_S exactly. Unfortunately, the monaco learning curve is not exactly flat, but let me give you an example.
I've attached a very basic monaco project for a single dashboard. Just unzip the attached zip to your computer, download the monaco binary.
First, you need to set up your environments.yaml file (sample included) to point to your Dynatrace environment. I use xxx12345 as a sample value. Also you need to name the environment variable from which monaco reads the API token for connecting to Dynatrace.
The project itself contains:
Monaco will create/update dashboard for each entry in the yaml with the values specified. This is how dashboard can be easily created and updated.