Mailchimp is whitelisted but emails still not forwarded

I setup a new Mailchimp account for our club (so we can send automated emails to guests and members).

However, in trying to verify our domain, it appears the confirmation emails from Mailchimp to our club contact alias are being bounced. I have tried our contact, admin, and individual officer email aliases. There are no issues using these (and sending to them from other random senders).

I have whitelisted @mailchimp.com in the email security admin settings to no avail.

I appreciate any insight on how we might resolve this. I would like to use our club email address as the "from" address in our Mailchimp campaigns.

Thank you!

You haven't provided your club number - so we can't do any investigation. Make sure that your contact address is enabled: Contact Forms tab in Email & Contact Forms module.

Club number is 8045. My apologies.

It is quite possible Mailchimp being generators of spam maybe blocked by other means that the blacklist.
You would need to provide us the IP address mailchimp is using to send the authorizations.

205.201.128.0/20
198.2.128.0/18
148.105.0.0/16

From:
mailchimp.com/about/ips/

Hi all - do you happen to have any advice on this? Thanks!