Can't you please share url of the site, so we can check it.
Maybe the color of the sublinks are black and over black backgorund they are not visible?
I guess you're previewing some theme, because on live site the submenu urls are okay
Yeah, I could see it, really strange issue.
I am just interested, why you are using JS solution for this simple type of dropdown, wasn't it better use css solution ?
By the way, in firefox it works properly, I could see issue in chrome but not in firefox.
I am now looking at it trying to understand what's wrong going there.