The 20-year-old, who lasted the entire duration in the first leg, believes they can achieve a double over the Black Dolphins at the Stade des Martyrs in Kinshasa.
"This game is obviously like decider for us because we need the points badly since we have only one game left at home," Amankwaa told Goal.
"We managed to win the first leg in Ghana which brought us to second place on the log so we wouldn't want to go down this time. Our target is to qualify to the next round of the competition so we must try to achieve a double or at least pick a point.
"Vita Club have a solid team and amazing supporters who cheer them on throughout the entire duration of their games but I strongly believe we will leave Kinshasa on Sunday without a defeat," he added.
Apart from Elvis Opoku, who is serving a ban through accumulated yellow cards and Derick Sasraku, who has been suspended indefinitely by coach Kenichi following his recent troubles at training ground, Aduana have no injury worries ahead of the game.