Hi dknights,
Based on your description, I understand that you cannot verify your domain using TXT or MX records.
We can only use TXT or MX record to verify domain. To help resolve this issue, could you provide the following information for us to troubleshoot?
1.Have you received any error messages when you verify the domain? If so, please post a screen shoot about the error message here for us to troubleshoot.
2.Which subscription of Office 365 are you using?
3.Did you verify your domain by following the steps in the links below? If no, please refer to the links below to verify your domain:
For Office 365 for small business:
Add your domain to Office 365 http://onlinehelp.microsoft.com/en-us/office365-smallbusinesses/ff637561.aspx
Verify a domain at a domain name registrar http://onlinehelp.microsoft.com/en-us/office365-smallbusinesses/gg584174.aspx
Change name server records at a domain registrar http://onlinehelp.microsoft.com/en-us/office365-smallbusinesses/gg549203.aspx
For Office 365 for enterprise:
Add your domain to Office 365 : http://onlinehelp.microsoft.com/en-us/office365-enterprises/ff637620.aspx
Verify a domain at any domain name registrar: http://onlinehelp.microsoft.com/en-us/office365-enterprises/gg584188.aspx
Edit DNS records for your Office 365 services : http://onlinehelp.microsoft.com/en-us/office365-enterprises/ff637620.aspx
A similar thread for your reference:
http://community.office365.com/en-us/forums/146/p/60177/223027.aspx
You can get more information about Troubleshoot domain verification issues in Office 365 by referring to the link below:
Troubleshoot domain verification issues in Office 365:
http://support.microsoft.com/kb/2515404
Thanks,
Linda Wang