I think this is the right guy. I did not find a P.F. Voigt but I did find a Phillip E. Voigt who lived in Rio Arriba County, NM (Chama) in 1920. He was born about 1868.
If this is the correct persoon either the census taker or the railroad clerk goofed. Voigt was the engineer on the last run of the Pagosa Springs Mixed. He ended his career on the Chili Line on a work train.
Voigt was hired on 1-06-1900 and promoted to engineer on 11-8-1900. That would have made him 32 years old at the time, which was rather old to begin an engine service career. That, and his rapid rise to engineer made me wonder if he didn't have previous engine service experience.
When the Pagosa Springs Mixed ended, Voigt could have taken a passenger job on Trains 115-116 out of Durango as he had seniority over regular engineers M.C. Fitzer and Owen House. Voigt passed over Fitzer, House, Lee Jorden, G.W. Moore, A.A. Wilkens, C.A. Kellogg and Charles Schonefield as an engineer. These men were all hired as firemen before Voigt.
An Alamosa-Chama run on Trains 115-116 would have opened up with the retirement of F.L. Hindle as well as the standard gauge passenger train to LaVeta.
Mr. Voigt had a relatively short career with the Rio Grande, 36 years but if Phillip E. Voigt was our man in question, he would have been 68 years old at retirement.
This is a case where additional research would be in order.