I looked at actual census images, Joe. After which I cast around for the William in my database. Alas, I believe I've found him, 1900, 1910, and later, but he's definitely not the one you need.
So you seem to have a bit of brick wall, not unlike a boy I once tracked who should have been on the 1880 census but at the age of 3 and a half was still un-named! Local orphanage records eventually solved that one, but that missing 1890 census is a bummer sometimes.
I suggest you try to find out when Texas first began keeping death records, find and get access to the microfilm of the appropriate years, and examine it carefully for all possible clues. For both William and for Rachel. If you're lucky, one or both of those death records may name one or both of the parents of the deceased. Also start trying for birth records of Rachel and William's children, guardianship documents, et cetera. And for goodness sake, question (again and again, if need be) your kin and step-kin for every possible clue! Sometimes they know more than they think they do.