The issue is that you are starting an OUT OF OFFICE agent for a Database that you are not the own. You do not have RUN OF BEHALF OFsecuity access to the server. This is in the servers document under security and on the right hand side under prgramability restrictions there is “Sign agents to run on behalf of someone else:”.
For the method you are using you need to be granted this access to the server or it wil fail.
Or Simply user the users ID to turn on OOO agent 🙂