I suggested where you went wrong - true Henry of Gourdon had a son Charles (that Gordon/Gourdon family was a major one) - however Henry states if his will that Charles was absent (and from words had been for some time 'if he comes' means that the son had been absent on at least a semipermanent basis "Fifthly, I leave and bequeath unto my son Charles Radcliffe the sum of five shillings as a legacy if he or any other person under him shall come to the Isle to demand the same or any right of my effects and to entirely exclude him from any further pretensions to my said effects. " - however look at the Charles + Mary Sayle - children every two years from c.1774 - no mention of Charles's kids in Henry's will - your only link is the name - the witnesses to the marriage don't help - also I cannot see any cross link between the families. A W Moore in his comments on Radcliffe's of Gordion makes no note of your Charles (which is strange as Charles + Mary's ch were still around in mid 19th C and thus should have been noted) - there is no point looking beyond this link until you have proved the connection which on face of it is wrong.