It may be possible to confirm family relationships by comparing test results with Al 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 37 markers, haplogroup RM269, FTDNA kit #686456
It is likely that these autosomal DNA test-takers will share some percentage of DNA with Al:
AncestryDNA, GEDmatch a628351[compare], Ancestry member scrollsaw65