Indirect vs. Direct Passage
If your ancestor arrived in Hull, they traveled the indirect route to the USA, and if they're in the Hamburg indexes, it will be in the Indirect Lists. The Hamburg-Amerika Line operated solely from the port of Hamburg. Arriving English passenger lists from the continental (domestic) trade are relatively nonexistent. The British Board of Trade only maintained passenger lists for international/transoceanic voyages. If your ancestors naturalized in the USA (after 1906), you may be able to obtain those records and possibly learn of the ship on which they sailed from England.
The other German port city during the age of the great migration was Bremen, and the shipping line operating from there was the Norddeutscher Lloyd (NDL). Bremen was heavily fire-bombed during WWII and the majority of the passenger lists from Bremen were destroyed.
Best of luck in your search,