Catalyzes the NAD(+)-dependent cleavage of saccharopine to L-lysine and 2-oxoglutarate, the final step in the alpha-aminoadipate (AAA) pathway for lysin biosynthesis. H2O + L-saccharopine + NAD(+) = 2-oxoglutarate + H(+) + L-lysine + NADH Amino-acid biosynthesis; L-lysine biosynthesis via AAA pathway; L-lysine from L-alpha-aminoadipate (fungal route): step 3/3. Monomer. Belongs to the AlaDH/PNT family. The coordinates of this ORF in the reference genome reflect non-intron adjustments made to compensate for presumed sequencing errors.