Hi Revae, I'd request copies of both of their obituaries. I'm not familiar with Sacramento or Riverside Counties but first check Random Acts Genealogical Kindness for a volunteer. Go to raogk.org/, read guidelines, choose California and choose Sacrmento or Riverside Co. Then look for a volunteer who will look up obituaries.
If that doesn't work out, Google the Sacramento County Public Library.
Elfie's social security death record shows her soc. sec. # was assigned in Texas. That might be a clue as to where she was from.
If they were married in Yolo County, contact the County Clerk-Recorder who registers all births, marriages and deaths in each county. Contact info can be found at kindredtrails.com/CA_Yolo.html . Successful Searching!