The best way would be to make a simple page plugin that loads it. You can copy the one from qa-plugin/example-page/ and in the process_request function, do something like this:
$qa_content = qa_content_prepare();
$qa_content['custom'] = file_get_contents('static.html');
Next, set the page plugin as your home page by adding this in qa-config.php:
'plugin-request' => '',
Where 'plugin-request' is whatever you set as the "Page slug" in the admin.