It may be possible to confirm family relationships by comparing test results with Phil or other carriers of his ancestors' Y-chromosome or mitochondrial DNA.
Y-chromosome DNA test-takers in his direct paternal line on WikiTree:
Family Tree DNA Y-DNA Test 67 markers, haplogroup R-M269, FTDNA kit #28986, MitoYDNA ID T11064[compare]
Mitochondrial DNA test-takers in the direct maternal line:
Family Tree DNA mtDNA Test HVR1 and HVR2, haplogroup U5, FTDNA kit #28986, MitoYDNA ID T11064[compare]
It is likely that these autosomal DNA test-takers will share some percentage of DNA with Phil: