Hi Jorose,
I believe the Edmonton marriage is for a different Joseph.
With the information that you gave for Emma Roberta's death, I found her Will, wherein she left her effects worth just over £105 to her husband Joseph Jesse Hunt; she died at Banstead Asylum but was previously living at Montefiore Street, Battersea.
Perhaps that explains why Joseph got married quickly.
I can't find a birth for Ellen Grimerson only on the 1891 census she was born 1872 in Gibraltar, her marriage cert says her father was Samuel Grimerson, a deceased soldier; she is 33 whilst Joseph is 47. The Helen on the 1901 census appears to be a different one as she was born in Woolwich.
On the US census what does Pa mean as regards emigration?
CR