Crystal Reports Comparing Fields

Message

   I have a report where I display the username of the person runing the report. I currently have it set as a subreport with a formula pulling from a DB I manually enter the users info into and comparing them to their login to see if the data matches and if so it displays their name and everything works. I am wanting to switch the data source of the DB to pull from a table that already exist in another ODBC connection the problem is one source lists the users as "domain\ID" and the other displays it as just their "ID" so it never sees a match. My current formulas in the subreport are:

in the recorcd selection

{Table1.EUID} = WebUserName

a formula I put in the report header inside a text box

if not isnull({Table1.EUID}) then 
    {Table1.Full_Name} 
else
    Right(WebUserName, InStr(WebUserName, "\")+1);

I then insert that as a subreport into the page header of the main report.

Thanks
KevV