Service Broker Using Wrong Certificates

After configuring two Service Broker instances that successfully send msg to remote server on separate databases, I am trying to set up a second service broker instance on one of the same, successful, databases. I am receiving errors on ssbdiagnose, only. No other tools show errors. 2 Errors from ssbdiagnose, when running on the source server. 1. 'target IP' 'targetDatabaseName' The certificate 'source cert name' used by user '' for dialog security is not deployed in the database. 2. 'target IP' 'targetDatabaseName' The user '' from sourceDatabase '' on 'source IP' cannot be mapped into this database using certificates. The source cert name from the first error msg is my previously existing certificate on the source server that is used to send msg to a different database on the target server. So it appears to be looking at the wrong certificate. When running ssbdiagnose on the target server, I get the following error: 1. Login Failed. The login is from an untrusted domain and cannot be used with Windows Authentication. Thank you