I think this is John (merchant) of Castletown's will (I have a note that Brian had it indexed under James taubman) -
dated 13 dec 1794;c'town;wife esther;only son john;dau christian cunningham w/o major wm (house called fitzgerald's house c'town);gdaus margt,isbel + dorothy taubman;gson major John taubman;gson John christian s/o dau margt;gson robert cunningham;names Nichols christian of Douglas s/o Francis christian decd;large bequests + ballahott;
Esther died about the same time - her will summary is
only son john;dau christian cunningham (w/o major wm already had marr settlement but also fitzgeralds house c'town);john taubman dead by probate
both in 1799 Malew episcopal
thus NO linkage to a henry