If you visit a URL with a folder but no file specified the browser looks for an index file called index.html, index.php, home.htm, etc.
In Pavlovia you will see that your html folder contains index.html which references your two js files. If you have more than two js files in that folder you should be able to reference the second pair in a slightly edited and renamed version of index.html
In PsychoPy in settings online you can specify a completed URL. Look at my crib sheet for how to add the participant expInfo to a URL