... well, actually it did!
It just never got aired outside Japan due to censorship concerns. The story deals about our friends Ash, Brock and Misty arriving at the zone, and learning a Dratini had been spotted there 30 years ago.
However, Kaiza, the parc guardian, isn`t to happy about it, and tells them the legendary Pokemon is no longer there, to prevent the parc being half destroyed like when it was first said the beast was there. Team Rocket intervenes however and Ash as a result nearly drowns, only to be saved by Dragonair who is happy to see it`s finder Kaiza again after all those decades.
That didn`t sound to bad now, doesn`t it. Well, the censorship commitee fell over these two moments:
Not really kiddie material indeed. Now, the episode in the original numbering was 35, so it took place shortly after the shipwreck series (with James`s Magikarp), but the numbering in Japan was different from ours, this episode taking actually place really at the beginning of the series in the japanese numbering.
For those wanting to see it, it`s still on YouTube with english dubs: