Toggle between read-only and allow user to drag seekbar

Hi All,

I'm creating a course were learners cannot skip to the next slide or chapter (restricted menu and restricted next/previous buttons) but I created a page for administrator when they enter a password the course will be unlocked (chapters, next and previous buttons). I'm using a read-only seekbar by default, is there a way to toggle that to user can drag with variables? If not is there a Javascript way?

I'm using the classic player in storyline 360, I tried setting readonlyOnce in frame.js to true which will allow users to drag seekbar after finishing the slide (which I don't really want) but I thought that this will allow admins to drag after they hit next then previous but it didn't really work, the seekbar has to go all the way to the end before they get the option to do that. Any suggestions?

Thanks,