In that case you can create a simple lookup. Something akin to (using my previously named examples):

my %csv_recipients = ( 
    'john_q_public@foobar.com' => 'a.csv',
    'jane_q_public@xyz.com' => 'b.csv',
    'some_other_address@example.com' => 'c.csv'
    # and so on
);
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Then to send it out just change your call to archive_results:

while (my ($recipient, $filename) = each %csv_recipients) {
    archive_results($recipient, $orig_file, $filename, $subject);
}
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or similar. Code untested, void where prohibited by law, et cetera et cetera ad nauseum.