I tried checking all of the Kibler families in Shenandoah County in the 1850 census and did not find him, nor an Amiss/Amos, etc.
It is noteworthy that he listed his place of birth in the 1880 census as Prussia (also the parents), and the 1870 census gives Hess. Ger.But most of the Kiblers in Shenandoah County and Page County, VA had been there for several generations already, which makes it puzzling. So I checked other spellings.
And there is a Frederick KUBE in adjacent Rockingham Co., VA in the 1850 census.He is shoemaker and 27 years old, born in VA (If this is correct) and living with theWilliam West family.
There are some Kubes in Orange Co., VA and Spotsylvania Co., VA. around 1850,60 & 70.