First of all, It is not a deal... Both of them trying to mock each other... They really meant nothing... After Aaliya proved that fan girl is obsessed with Abhi, she came to Pragya and talks over confidently that she cannot prove her wrong and you don't have any option to stop mehendi now, so I am giving you offer... She was clearly mocks Pragya... Pragya knows she will never fulfill the deal , so she mocks her with counter offer...
Even if Pragya left by taking her offer, then also Aaliya will not stop Tabhi's marriage... If you noticed the conversation between Taaliya in next episode, Tanu asked Aaliya why do you offered deal for Pragya, and Aaliya said if Pragya left, then what is the need of mehendi and sangeet, straightaway we will do marriage for you and Abhi... This is the mentality of Aaliya... And As for Aaliya, she will never go against Tanu because she is always partner in her crime... I think she can't take risk by ditching Tanu...
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