Re: "don't have access, or it does not exist." Pages on the old community site that didn't have any activity within the last 3 years were not transferred to this new site. In other words, that content is no longer available.
Re: "jumping to Slide %Variable%." The "jump to slide" trigger only accepts "prev slide," "next slide," or a specified slide.
However, you can add multiple triggers to the Next button that jump to different slides, and use trigger conditions so a given trigger will only run if the specified conditions are met. Those conditions could check variable values.
See this post for examples: TIP: Let the user choose their path | Articulate - Community