How can we say that the Garuda Purana verse glorifying the Bhagavatam refers certainly to Bhagavatam as we have it (and not pre-edited version written by Vyasadeva)?

From Kanai Krishna P

I heard your answer to a question about Bhagavatam being natural commentary on Vedanta Sutra. There’s a famous reference from Garuda Purana which says ‘arthoyam brahmasutranam…'(quoted in CC Madhya 25.143-144)This reference speaks of number of verses in Bhagavatam as 18000. Can we say that this reference is certainly speaking of Bhagavatam as we have it(and not pre-edited version written by Vyasadeva)?