The result gave the Royals a 164-134 triumph on aggregate.
Tyresa Smith and Petra Manakova scored 13 points apiece and Romy Bär added 12 for the hosts in Game 2.
Any hopes Dexia had of getting back into the game after their 95-71 first-leg defeat evaporated in the opening quarter when they were outscored 22-14.
Also advancing on Wednesday were Botas Spor, despite a 69-64 defeat at CCC Polkowice.
Amisha Carter had 22 points and 10 rebounds for the Polish club, which suffered a 138-119 defeat on aggregate.
Courtney Lynne Paris, the USA international, had 23 points and 14 rebounds for Botas Spor.