use HTML::TreeBuilder;
use Data::Dumper;
use 5.16.0;
my $h = HTML::TreeBuilder->new;
$h->parse_content( do{ local $/; } );
my @tables = $h->look_down('_tag' => 'table');
# The desired table is the firet table nested in the outer table.
# $tables[0] is the outer table and $tables[1] is the first nested
my $table = $tables[1];
my @headers = map { $_->content } $table->look_down( _tag => 'td', class => qr/HeaderTitle\b?/ );
print Dumper \@headers;
__DATA__
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