The Elephants lost 5-4 on penalties after a goal-less draw after extra time in Douala, with Cornet scoring a supremely confident spot kick in the shoot out.
That was in vain, however, as Mohamed Salah scored the deciding penalty after Eric Bailly’s earlier miss for Ivory Coast.
Cornet came on for Ajax’s former West Ham forward Sebastien Haller just before the second half of extra time, as Ivory Coast looked to break the deadlock.
It was only Cornet’s second appearance of the finals, after featuring in the opening group win over Equatorial Guinea.
He will now return from Cameroon, in time to face the Hornets at Turf Moor a week on Saturday.
Cornet came on for Ajax’s former West Ham forward Sebastien Haller just before the second half of extra time, as Ivory Coast looked to break the deadlock.