Obi said he received the news shortly before the game last Tuesday.
Nigeria has failed to pay its players on time on several occasions in recent months.
Mourinho was sacked by Chelsea in December 2015.
The Paralympic team has already dwarfed the Olympians' medal haul.
The Nigeria captain tells Newsweek about his medal joy and how the country's football federation can do better.
Nigeria's footballers will now face Honduras in the bronze-medal match.
The Nigeria captain tells Newsweek that the 2016 team can emulate the 1996 Olympic heroes.