Edge transport doesn't talk to 2013 but works just fine with 2010

I could not get my Exchange 2010 Edge Transport to talk to my new Exchange 2013 server.  The Edge Transport continued to function just fine with Exchange 2010.  All the mail from my new 2013 box that was supposed to be going through the Edge Transport was just sitting in the mail queue.  I could see MSExchange EdgeSync 1032 errors in the logs.  I was also getting MSexchangeTransport 12023 errors in the event logs.  These two issues are related but I didn't know it last week when I found out that I was queuing mail.  I had to make a workaround to get mail flowing.  It wasn't until today that I fixed one and that lead me to a useful error of MSExchange EdgeSync 1033 that gave a certificate error.

I had to run
Enable-ExchangeCertificate -Thumbprint <thumbprint> -Services SMTP
to clear MSexchangeTransport 12023 error.  Using the ECP to set the "already set" SMTP flag did not work and no error or information was shown.  Running that command from EMS asked if I wanted to replace the default SMTP certificate. I answered yes and it told me there was an Edge Transport problem and to resubscribe.  Below is a partial screenshot.

I did the resubscription and all is good now.  Now I just have to tear down my workaround.