Remove IP addresses from Order Confirmation Email

I need to remove the lines below from my order confirmation e-mails. Apparently e-mails are being blocked based on the content of these two lines. This just started happening recently and site has been active for years. I am using text e-mails. I can't seem to find where the actual addresses are being populated. I did find the text constants in includes/languages/English/email_extras.php but I need to remove the addresses also. Any help would be appreciated. Thanks!

These are located in the "Office Use Only" section.

IP Address: 0.0.0.0 - 0.0.0.0
Host Address: c-0-0-0-0.hsd1.md.comcast.net

It is only admin emails that get that information put there.

1. You should ask your hosting company why those emails are being blocked.

2. Then consider using SMTPAUTH as your email-transport method in your Admin settings, in case they're rejecting them because your emails aren't from an authenticated source.

3. As a LAST resort you could change the code in email_collect_extra_info() in functions_email.php

I am already using SMTPAUTH. I have spoken to the hosting company several times and they do not know why the e-mails are not reaching destination. All their logs show that the e-mails are sent out successfully. By forwarding the offending e-mails and deleting one line at a time it appears that the lines mentioned in my original post are what is causing the blocks. Could you suggest the changes I would make to the email_collect_extra_info() section to accomplish this?