For some reason, your site is rendering the javascript incorrectly. There is a double quote in the onclick call where it should be a single quote.
Why is this? I couldn’t begin to tell you. It’s correct in the plugin and also in testing. There are too many external possibilities for me to give you a specific answer – theme, some other plugin, etc.
I’d suggest just switching to use the TOS shortcode to set up a TOS page that the plugin will link to. This is described in the User Guide section on shortcodes – it is one of the “page” shortcodes. That will avoid the javascript onclick which will save you the effort of trying to trace why it is incorrectly rendered.
(Incidentally, I noticed other things in your site that are incorrectly rendered outside of this plugin as well – there is a <div> and <style> tag in your document <head> which is also not right, so you have problems outside of this…)
