Captain John Mikel Obi and young Deportivo La Coruna goalkeeper Francis Uzoho as well as Chippa United custodian Daniel Akpeyi are expected to arrive camp on Tuesday.
Omeruo, who was placed on the standby list by Rohr reported to the Eagles’camp in Rabat on Monday after he was asked to replace Ogenyi Onazi.
China-based striker, Odion Ighalo and Chelsea wing-back Victor Moses have long been ruled out of the clashes due to injuries.
The Nigeria Football Federation, while confirming the development on their official website on Monday, said 15 players had arrived in Rabat.
Ahmed Musa, Wilfred Ndidi, Mikel Agu and goalkeeper Ikechukwu Ezenwa arrived in Morocco with the coaching staff on Sunday.
Other players who reported on Monday are Oghenekaro Etebo, Alex Iwobi, Henry Onyekuru, Chidiebere Nwakali, Kelechi Iheanacho, Uche Agbo, Chidozie Awaziem, John Ogu and Anthony Nwakaeme.
The Eagles have already qualified for Russia 2018 after winning four of their five qualifiers to lead Group B, which also houses African champions Cameroon and Zambia, on 13 points.
However, Rohr has promised to field a strong team for the Constantine encounter at Stade Mohamed Hamlaoui.
On Saturday, the Nigerian team will fly aboard a chartered flight to Krasnodar for a friendly against Argentina.