I found John and family in 1850 living in Stark County, IL too. I'd look in Stark Co or Iowa, Doniphan, Kansas Territory for his death info.
In 1883 a W. H. Wolf was living in Whitman Co., WA. Born=abt. 1852, IL, married.
In 1885 a Nancy Wolf, 63, was living in Whitman Co., WA. Born-abt. 1822, OH.
I checked Washington State Digital Archives but I didn't find any death info for any of these family members.
However, deaths weren't recorded at that time. I suggest that YOu contact the Whitman County Genealogical Society, rootsweb.com/~wawcgs/res.htm . They have a County Death Register from 1891-1907 with deaths extracted from the Pullman Herald Newspaper 1888-1929.
They also have a County Marriage Records 1872-1897 and probate records 1869-1902.
In 1880 John C. Wolf and family were living in Whitman Co., WA.
John C. Wolf, b. IL, blacksmith-trader, 34.
Cynthia, wife, b. OH, 32.
Robert, b. KS, 10.
Neva, b. KS, 7.
Ada, b. Wash. Terr., 8 months.
Edward Calolian, servant, laborer, b. IL, 17.
In 1910 John and Cinthia [spelling per indexer] were living in Moscow, Latah Co., ID.
John C. Wolf, b. IL, 64, marr 41 yrs, father born-PA, mother born=OH, merchant grocery store.
Cinthia E., b. OH, 61, had given birth to four children but only three alive in 1910.
I checked the death index for Idaho but neither John nor Cinthia or their children were listed.
Regarding the John and Cinthia Wolf family who lived in Moscow, Latah Co., ID in 1910, I'd contact Random Acts Genealogical Kindness to find a volunteer in that County.
Go to raogk.org, read guidelines, choose Idaho, choose Latah Co. and ask Barbara to look for their death info & any other info about their children.
Latah Co. does not have a genealogy society but they do have Latah County Historical Society. Go to latah.id.us/historicalsociety/ and check out their web site and ask them if they do any research. Successful Searching!