"1) Is there a way to look at all the names of persons who sailed on a
certain ship on a certain date?
2) Is there a listing of all the ships that sailed to Ellis Island or any
other method to confirm that information regarding a ship arrival on
naturalization papers is indeed accurate?"
Sure, look at the manifest, and you will see all the passengers on that ship
on that date; you can usually do that at the EIDB. You can get a listing on
microfilm of all the ships that sailed into New York >from the FHL or
NARA-but what that will tell you I don't know.