The pages you are linking use two different characters, one is the &mdash and the other I don’t know the name, it does not translates into an Html entity…
Original:
2——-2——-7——-7——-| <– Mixed characters
Using the character that works:
2---2---7---7---| <– This one is not &mdash.
You may consider using a shortcode to encapsulate the tabs, so you can manipulate the characters and substitute faulty ones.