Hello,

1°
It looks like the localhost is not reachable on that URL to access the file proxy.php used to play the audio, but i've not clue on this because never happened. Firstly try to check if the URL is reachable opening in the browser, if not investigate in the htaccess, etc to find why it's 404 {site_url}/plugins/system/screenreader/screenreader/libraries/tts/proxy.php?lang=pt&engine_token=0&token=d441183084d35f7fa9290c2b09e634aa&text=Lorem%20ipsum.

2° Yes if you solve the problem excluding the jQuery inclusion of the Screen Reader is ok, however if you are using Joomla 3 only 1 instance of jQuery should be included in the page like the one called by the Screen Reader.

Best regards