Processing a cursor of 11,000 rows and Query completed with errors

Before we even get to why you're running so slow, execute this:

DECLARE @SQLString NVARCHAR(MAX), @NewLineChar CHAR(1) = CHAR(10)
                SET     @SQLString      =       'INSERT INTO    [dbo].[FBMCNameMatch]'                                  +   @NewLineChar;
                SET     @SQLString      =       '                               ('                                                                              +   @NewLineChar;
                SET     @SQLString      =       '                               [FBMCMemberKey],'                                               +   @NewLineChar;
                SET     @SQLString      =       '                               [HFHPMemberNbr]'                                                +   @NewLineChar;
                SET     @SQLString      =       '                               )'                                                                              +   @NewLineChar;
                SET     @SQLString      =       'SELECT         ';


PRINT @SQLString

Your insert is being chewed up because you're not concatenating it... you're setting it to a new value each time...

It's good practice to SELECT your variables and inspect their values when you're doing dSQL like this.

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