Philosophically, you could make the argument that it really does exist.
It isn't an island, despite having Island in the name. But that's true of Coney Island as well, and it also exists.
A closer analogy might be Vancouver's False Creek, which as the name suggests is not a creek (it's a tidal inlet).
Pine Island in New York State is both not an island, nor named after one, it's just slightly elevated.
Point is there's precedent.
Chelsea Creek in Boston empties Mill Creek.
https://www.kqed.org/news/11983858/alameda-the-island-that-a...
It's only barely one today.