I'm interested in the origin of surnames so, seeing this thread, I looked Whichello up online and found this statement, apparently written by Chloe-Jasmine in 2011, in response to someone with the same surname who was asking her if she knew where it came from. This is what she herself appears to have written in response.
"It’s a very curious one, as the vast majority of Whichellos are spread out in America, Australia and England ( Often people ask me if it was coined in Italy, simply because of the “O”). It is, as far as I know , derived from ‘wic’ -the dweller in the village hamlet or town. I have always been led to believe it stemmed from the Vikings in Scandinavia who settled into Village life in Britain ( I am of Norwegian/British blood myself). There have been other versions of the spelling (such as Whichelow, ‘Whittokeslowe”Witokeslawa’,hovering round in medieval England which predated the Domesday Book of 1086. The origin of the name “Whichello” has always fascinated my brother, who has done extensive research into it ."
Having myself looked into various 'English' names from the 13/14th centuries and before, many of which came from other lands, this sounds very feasible to me.