If you can find evidence that the quests were completed before December 3rd, 2001 (ie. the
last patch), you should make a post in the Bugs forum with that evidence. If your evidence is solid, the staff will almost certainly implement those quests here.
If you can't, you're essentially asking for custom content. Many players (myself included) think it'd be fun if the staff made custom content "continuations" of classic quest lines, like the Shawl or the Iksar Cudgel. However ...
A) The staff has given no timeline on custom content, and it could be years away
B) The staff has not indicated whether they will continue quest lines
C) Even if they do continue them, they may very well make their own (new) versions, not the version on live