Yes, but it's likely you're not going to like it...

Install Text::CSV, and use the following script:

#!/usr/bin/perl
#
use strict;
use warnings;
use Text::CSV;

$ARGV[0] or die "Usage: $0 <filename> [<filename>] ...";

my ( $template_file_name, $templateText, %hash ) = '';

my $csv = Text::CSV->new( { binary => 1, eol => $/ } )
  or die "Cannot use CSV: " . Text::CSV->error_diag();

for my $csvFile (@ARGV) {
    print "\nProcesing file $csvFile ...\n";
    open my $csvfh, '<:crlf', $csvFile or die "Unable to open $csvFile
+: $!";

    # Ignore column names in first line
    my $columnNames = $csv->getline($csvfh);

    # Get vars from second line
    my @vars = @{ $csv->getline($csvfh) };

    # Process each csv line
    while ( my $row = $csv->getline($csvfh) ) {
        my $templateFN = pop @$row;

        if ( $template_file_name ne $templateFN ) {
            $template_file_name = $templateFN;
            undef $templateText;
        }
        
        # keys: fields from second line; values: fields from csv line
        @hash{@vars} = @$row;

        $templateText //= getTemplateText($template_file_name);
        my $templateTextCopy = $templateText;

        $templateTextCopy =~ s/$_/$hash{$_}/g for keys %hash;

        my $ofile_name = $hash{'##rtrname##'} . '.txt';

        print "Writing to file: $ofile_name\n";
        open my $fh, '>', $ofile_name or die "$ofile_name: $!";
        print $fh $templateTextCopy;
        close $fh;
    }

    close $csvfh;
}

print "\nDone!\n";

sub getTemplateText {
    my ($template_file_name) = @_;

    local $/;
    open my $fh, '<', $template_file_name or die "$template_file_name:
+ $!";
    $templateText = <$fh>;
    close $fh;

    return $templateText;
}
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If you try it on one machine and it resolves the uninitialized error issue, then there's more diagnostic information to work with.