The national federation announced coach Stephen Keshi had kept the 23 players called up for the 2-1 first-leg win in Addis Ababa last month and added the British-based pair.
Nigeria are strong favourites to qualify for the World Cup for a fifth time.
Omeruo, who returns after a shoulder injury sustained at the Confederations Cup in Brazil in June, was loaned by Chelsea to Dutch club ADO Den Haag last season but is now back with the London team.
The 20-year-old defender played all six matches when Nigeria won the African Nations Cup in South Africa at the start of the year.
Defenders: Efe Ambrose (Celtic), Francis Benjamin (Heartland), Elderson Echiejile (Braga), Azubuike Egwuekwe (Warri Wolves), Solomon Kwambe (Sunshine Stars), Godfrey Oboabona (Rizespor), James Okwuosa (Chippa United), Kenneth Omeruo (Chelsea)
Midfielders: Reuben Gabriel (Kilmarnock), Nosa Igiebor (Real Betis), Victor Moses (Liverpool), John Obi Mikel (Chelsea), Nnamdi Oduamadi (Brescia), John Ogu (Academica), Ogenyi Onazi (Lazio), Sunday Mba (Enugu Rangers)