As far as I can see from the console, you can both change the DNS servers (if you don't like Google's ones) and edit the zone file. So, I guess, you could suppo

As far as I can see from the console, you can both change the DNS servers (if you don't like Google's ones) and edit the zone file. So, I guess, you could support DKIM via another SMTP, e.g. Amazon SES. (please note that I have no affiliation with G domains, I'm just trying to reply to the original question to the best of my knowledge)