I have no idea re: the 2 wives. Perhaps he was md 2x--maybe the first one died. I see no entry in Arbory or Malew burial records for any of these Wilsons.
They seem to have left IOM after Martha in 1863 and before the 1871 census.
Children were baptised in Malew, family lived in Arbory.
1851 Census
Arbory
Balladoole
Miles Wilson head married 34 ag labourer b England
Cath wife married 32 b Malew
Sarah dau 4 scholar b Arbory
John Jos son 1 b Arbory

1861 Census Index
Arbory 1 92
WILSON
Miles 45 b England
Catherine 44 b Malew
John 11 b Arbory
Margaret 7 b Arbory
Rebecca 4 b Arbory
Sarah 18 b Arbory