it seems it doesn't like looking for a class name

In what way does it not like it? As long as you initialise the module with the attributes you want it should not have a problem:

my $te = HTML::TableExtract->new( attribs=> { class=>'class-name' } );
$te->parse($html_string);
for my $ts ($te->tables) {
    print "Table with class 'class-name' found\n";
}
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