This is true of a great deal of content throughout the game. Even worse i've been told that not all arcs are included in Oro. There have been many proposed solutions to this issue. The general consensus is that it would be a great deal of effort to scale up foes to match a characters increasing level. Then again there's always exemping a team down to match the content levels. Keep in mind the HC squad is small. They have a lot going on between balancing powers, creating new powers, animations, sound, bugs, costumes and new enhancements. For now use oro, as that is the original solution to finish outleved arc. While it is not perfect
Bugged quests
Cant invite others mid arc
missing quests
It is better than nothing. I too enjoy the unique and nostalgic storylines or the olden times. Perhaps we will meet up one to day kil skuls