“Missing” owners in the owner section of the TMK data will likely be found in the Sale Grantee section. 

Here are the steps to run a Sale Grantee search. The Sale Grantee search field is located in the main field page under the People section.
Simply expand the People section and use the Sale Grantee field.

Enter your search as Last, First name.

You may also locate the Sale Grantee search field with Add Fields

ETAL  =  Et al. =  Short for et alia, a Latin phrase meaning “and the others”.
Example: