GO:0052917: dol-P-Man:Man(7)GlcNAc(2)-PP-Dol alpha-1,6-mannosyltransferase activity
Catalysis of the reaction: alpha-D-man-(1->2)-alpha-D-Man-(1->2)-alpha-D-Man-(1->3)-(alpha-D-Man-(1->2)-alpha-D-Man-(1->3)-alpha-D-Man-(1->6))-beta-D-Man-(1->4)-beta-D-GlcNAc-(1->4)-D-GlcNAc-diphosphodolichol + dolichyl D-mannosyl phosphate = H(+) + alpha-D-Man-(1->2)-alpha-D-Man-(1->2)-alpha-D-Man-(1->3)-(alpha-D-Man-(1->2)-alpha-D-Man-(1->3)-(alpha-D-Man-(1->6))-alpha-D-Man-(1->6))-beta-D-Man-(1->4)-beta-D-GlcNAc-(1->4)-D-GlcNAc-diphosphodolichol + dolichyl phosphate.