> Really annoying that my email server IP has never sent anything, no relay, no spam, almost no traffic so what is stated is not true and even their own tools reports nothing.
> Is Google looking at MAC addresses to do this?  How can we stop it?   I really do not want to run another server just for tor as that costs!

I don't think its you Tor node - it just google. I note that your DMARC, SPF, etc are set and valid. You mail server is not an open relay. I maintain a few mail servers and run into these types of problems. There is no real reason for them. Microsoft is the worst - no logic what so ever. Do others use your server and has one of those accounts been compromised? Had one last week - a user followed a spam link and gave out their username and password - we sent 300000 emails out in an hour... You don't need to be on black lists to be blocked by the major players. You might want to relax your DMARC to see what happens.

Paul