Regarding the correct surname of Alancoates-8, under the prevailing style at Wikitree I believe it should be "Parker a.k.a. le Parker, de Alcancoates". That is, his full formal surname at the time was "le Parker de Alcancoates" (i.e. it followed the style of the Norman/French aristocracy, so that the last word is a geographical affix).
His father's surname was le Parcar/le Parquier and the family eventually dropped "de Alcancoates" and "le", to become simply Parker.