I have had a look this morning and found out a few things that may help
Based on the death of Mary Anne I wondered if Charles would have moved or remarried
There is a Charles Deardon living in Yorkshire on the UK census returns from 1881
1881 in Pickering, Turn Hill, Hartoft With Turnhill, Yorkshire with a Watson Family; shown as a widower and a clogger (wooden shoemaker) aged 40
1891 at Spires Farm, Morley Terrace, Cropton, Yorkshire as head with lodgers aged 50
1891 at Middleton Road Southside, Middleton alone aged 60
no obvious match in 1901
There are no children listed on any of these records
However they all show him as born in Rochdale and if you go back to the 1841 census; in Green, Rochdale, Wuerdale & Wardle; there is a Samuel Deardon aged 20 a labourer with his wife Betty, same age with a 4 month old Charles; also listed are Alice 15, Betty 13 and Sarah 8 presumably his sisters.
There is a marriage record in 1840 Rochdale, Lancashire Jul-Sep Vol 21 Page 420 for Samuel DEARDON with a possibilty of 4 matches one being Betty WIDDUP others Ann, Alice or Rebecca.
There seems to be no immediate sign of Hugh, James or Mary Jane either in England or Ireland.
I would think the record that looks like Hugh having a twin is only referring to his middle name but equally wouldn't rule it out.