Domain authentication with MailChimp

Hi folks,

I'm trying to authentic our domain (fraservalleyirishdance.com).  MailChimp says to add the following domain records:

CNAME1 k2._domainkey dkim2.mcsv.net

CNAME2 k3._domainkey dkim3.mcsv.net

TXT         _dmarc              v=DMARC1; p=none;

It seems like homestead doesn't like the underscores in there (or so I've read)?  Is there any way you can set them manually?  Going to Cloudflare (or similar) is a bit overkill for us.