Just in case anyone has an issue with this, the rke2-install module expects the user to have an ssh key loaded in their ssh-agent keys to talk to the server where it will install rke2. I have had some issues in the past when many different keys are loaded into the agent, if you have an issue where the key is in your agent, but it doesn't seem to be using it, try making sure that the correct key is one of the first 3 keys in your agent.