Hi Chris, unfortunately this is not going to be possible with Docker pipelines. You either need privileged mode to run docker-in-docker, or you need to mount the host machine docker socket, both of which required trusted mode.
If you cannot use trusted mode, the best option is to use a VM for your pipeline. We provide a digital ocean runner that creates a dedicated VM for you pipeline. Inside the VM you can do whatever you want. Announcing Digital Ocean Pipelines