Thanks for the info on Folkestone Library. I will try to get there as soon as I can.
In the meantime I have this from New Zealand contact -
1) . George Matson
    ~Archives, Hobart, People Index~ 
      George Matson married Frederica Christine Sievwright, Holy Trinity  15.7.1858 
       Mrs George at the Bank of Australia, a son 12.11.1860 (Pioneer  Index)
       Pioneer index
       Tasmanian Archives
BDM
George MATSON m 1858 Hobart Frederika Christina  SIEVEWRIGHT
Children
Charles George MATSON 1859                     no chdn listed
Frederick Manley MATSON 1860                  no chdn listed
Robert Stephen Cliss MATSON  1863           no chdn listed 
Major Cricket teams Tasmania  George MATSON 1853-1859 born 5 Dec  1817 Rochester, Kent England. died 22 July 1898  Brighton, Sussex England  (Which you had already found at 
http://cricketarchive.com/Archive/Players/2/2626/2626.html) 
I  thought I had seen an early death date for Frederika Christina so below could  be the same George with a 2nd wife. 
BANK OF AUSTRALASIA - Auckland  Branch - Manager - George MATSON 1 Mar 1864
1867-8~New NZ Directory~G Matson, Manager Bank of  Australasia, Auckland; residence Remuera
1898 George Matson Brighton, Surrey Gentleman d  22.7.1898 
Probate 6158 W AK filed 20 8 1898 h/o Louisa f/o  Charles George Matson of Watford England 
Owned South Western portion of allotment 131 of parish  of Tautaroa County of Whangarei 40 acres valued at £40 left to wife Louisa  
2)  Was Henry Matson's 'uncle' James at Bacchus Marsh actually his  brother James Moon Matson?
      Probably Henry Manifold  MATSON's uncle and Henry MATSON's brother. 
 CD-Rom State Library Melbourne - Pioneer index
Sarah Jane d/o James Matson and Martha Graham    b Edge              1870
James Graham s/o “     “                       “           “           b Malmsbury    1873
Margaret Marie d/o     “                       “           “           b Tr Ar                         1875
Isaac Carroll     s/o         “                       “           “           b Tr Ar                         1878
Martha Catherine d/o    “                      “           “           b Morw            1885 
So it seems we have agreement that the book by W. J. Manifold looks wrong and it was indeed James Moon Matson who had the family in 2) above.
So many thanks Valda on a great piece of detective work! 
 
The will of Richard Rogers seems unlinked as far as I can tell. 
I have found a Mary Matson of Sandwich, daughter of a late John Matson. She was christened 29th October 1776 and the daughter of John (1746-1805) and Mary Roberta Harvey (1750-1812). However there is a  Will for a Mary Matson of Sandwich at Archdeaconry Court 1810. 532 Book 103 which may also refer to that Mary. For the moment I will leave that to one side.
Incidentally, I know it's not her mother Mary Roberta's as her's is 'Will of Mary Roberta Matson, Widow of Sandwich, Kent. 19th November 1812. (Prob11/1538)'
My focus is to try to identify the father of Robert (1786-1865). As we have already said, it seems that common practice is to name eldest son after father and so we need to try to find the christening of Robert (1741-1820) who married Elizabeth Pilcher at Swingfield in 1781. All we know is that he seems on the older side (40) and from the marriage licence - Canterbury Marriage licences 10th November 1781-
"Robert Matson of Swingfield aged 40 yeoman bachelor and Eliz. Pilcher spinster of the same parish aged 30".
Taking in to account your earlier comment about residency (
when you marry you of course only needed three weeks residency in a parish to be of that parish. So adult Robert of Rochester'marriage in 1808 when he was of Ringwould is merely stating that that was where he had lived for the three weeks prior to his marriage, but gives no indication how long he had lived there prior to those three weeks. Between birth and marriage people could move quite a distance. Swingfield is close to Folkestone which is just around the coast from Dover.) has made me wonder if the same could have applied to the husband of Elizabeth Pilcher?
I wonder if there is a birth for a Robert Matson about 1741 in another parish? At the moment I don't have one. 
Do you by any chance have anything about East Langdon where we have a James Matson marrying Ann Arnold in 1767?
I hadn't thought about the date when Robert wrote his Will, (
if Robert Matson wrote his will in 1783 shortly after his marriage and never updated it, if he did have children it is not surprising they are not mentioned in such an early written will. and that's a good point. So it again seems reasonable as a fit.