Warren Ancestor MIA

Hi Everyone,

I am having at terrible time tracing my mother's paternal line beyond my grandfather. I have a few details relating to my Great Grandfather but they all result in dead ends and I am out of ideas for how to make any progress. Any advice or information you can help me with would be very much appreciated. 

Here are the records we have for him:

1. Marriage Certificate January 1898: Frederick James Warren. 38 years old. Born Battersea, Surrey, England approx. 1860. Father is Benjamin Warren, deceased. Occupation: Boilermakers Assistant. Resides 2 Corunna Place. 
2. British Army Service Record April 1890: Militia Attestation Record. Frederick James Warren. 28 yrs, 10 months old. Born Battersea, Surrey England. Occupation Hammerman. Employer L.C. & Dover Rail Co. Locomotive Dept. (Mr. Spencer, Manager). Single, Resides (for 11 years) at 2 Brewery Cottages, Brewery St. Wandsworth Rd. On next page, his appearance is described. Nothing notable other than two ring tattoos, middle finger, left hand. Reports for annual training as a Royal Fusilier until 1908, when he is discharged in "Fair Character". 

The story goes...FJW was married to Elizabeth Coughtrey in  Jan 1898.  They have a son, Richard Frederick Warren in November 1898. In 1902, Elizabeth emigrates to Canada with William "Henry" Warren. They leave Richard behind in the care of Elizabeth's family. Relatives have been told that Frederick and William Henry are brothers. No wedding certificate exists for Elizabeth and Henry. Upon arrival in Canada, Henry becomes an architect and they run boarding houses. 

I have taken an Ancestry DNA test. I am working on leads through that. I am also obtaining a DNA test sample from Henry Warren's grandson in the hopes that this may provide more information. 

Thank you for anything you can do to help. 

A