He isn't in the Maughold reg baptisms - the first Benson is James son of William Benson & Esther Kneal bapt 15 Sep 1811. Also no illegitimate William without a named father around the dates you gave. He could have been bapt in Ramsey, or appear in non-conformist records.

William BENSON 66 [place] Ballakilley buried Maughold 29 Apr 1859
Esther BENSON 78 Balla Killey buried Maughold Mar 25 1864

The first Maughold burial for Benson was:
Francis infant Son of ____ BENSON Sep 19 1825
Then: William BENSON 6 years Jun 10 1848

Sue