You may have to work with Tech Support on this question. I do not know whether it is possible to have 2 separate strings in a SAS TITLE statement behave the way you want with TAGSETS.EXCELXP. For example, if you compare the behavior of the ODS HTML output with the ODS MSOFFICE2K output with regard to the text strings in the program below, you will see the the Microsoft "flavor" of HTML exhibits the same behavior as the Microsoft "flavor" of XML.
ods html file='c:\temp\testtitle_ht4.xls' style=sasweb;
ods msoffice2k file='c:\temp\testitle_mso.xls' style=sasweb;
ods tagsets.excelxp file='c:\temp\testtitle.xls' style=sasweb
OPTIONS( embedded_titles='yes' embedded_footnotes='yes' Autofit_Height= 'YES' );
title1 j=left color=black underline=1 "I.L.D INSURANCE CO. LTD " j=center color=black "BORDERAU FOR REINSURANCE FOR MARCH";
proc print data=sashelp.shoes(obs=5);
var region subsidiary product sales inventory returns;
ods _all_ close;
So it seems to be a Microsoft-specific interpretation of the text strings that makes this behavior happen. However, if I just insert some extra spaces in the title string, as shown below (instead of 2 separate quoted strings) -- Excel and TAGSETS.EXCELXP seem to respect the extra spaces.