Can Storm: Neutralized Retrieve Morlocks Specials from under the Morlock Tunnels Battlesite?

Yes, however, if the OPD under the Battlesite is a Morlocks special, Storm cannot retrieve it. The total number of Activators must still be equal to the number of Special Cards under the Battlesite, though.
EXAMPLE: If there are 3 Morlocks Special Cards and 3 Storm Special Cards under the Battlesite, there must be a total of 6 Morlocks or Storm Activators. There can be 1 Morlocks, 2 Storm: Neutralized and 3 Storms; 1 Morlocks, 4 Storm: Neutralized and 1 Storm, but not 3 Morlocks, 3 Storms and 3 Storm: Neutralized.

Can I use Morlocks non-OPD special under the Wakanda or X-World Battlesites, as long as I have Storm: Neutralized Activators to draw them?

Yes.

Can I use Storm: Neutralized to draw Morlocks Special Cards from underneath the Sewer Battlesite?

No, because Storm is not listed on that Battlesite. Only Characters which could be used on that Battlesite as a homebase can be used as Activators.

If I am playing Storm: Neutralized on my team, can I still use the Sewer as my Battlesite?

Yes, but no non-OPD Morlock Special Cards may be played, as they can be put in the deck.

Do Storm: Neutralized Activators duplicate with Storm and Morlocks Activators?

They duplicate with Storm and Storm: Bloodstorm Activators, but not with Morlocks Activators.

Do they duplicate with Storm: Bloodstorm Activators?

Please carefully re-read the above.

Why on earth did Storm have a mohawk?

Because Chris Claremont is weird old man.