Hello Anne

Are you saying that the James Edward ch 20/11/1864 in Lonan is not yours ?
There are many James Collister/Callisters and a few James Edward's born on the IOM in that period , but he is the only James Edward with father William, and he was christened Lonan.
Did you find them in England on the 1871 Census ? That should confirm his mother's name.
Cheers
David