Running SQL job: The login is from an untrusted domain and cannot be used with Windows authentication
The job is executed as the SQL Agent account, unless you have configured a proxy.  The owner of the job is irrelevant as long as the SQL Agent account can verify that the owner is valid (still exists in AD/SQL).  

Verify which account is running the job, either the SQL Agent account or the Proxy account. Then verify that account has permissions into the linked server.  Or create a proxy account for this job.