Just to add a few points here.
Radha, of course does not feature anywhere in SB, so her giving gyan to Uddhava is is an example of the Creatives' creativity.
In fact the Sagars have given a different perspective altogether . Nowhere in SB is the Prem Vs Gyan angle brought in. Uddhava was a highly realized person, who because of his gyan and reverence for Krishna saw the inherent divinity in the Gopis' love for Krishna. He was not sent to Vrindavan to be 'converted'
Uddhava, on Krishna's orders comes to Vrindavan with his message. He meets the gopis and is delighted to see them constantly thinking about Krishna. Udhava delivers Krishna's message.
They spend a few months talking about Krishna. Uddhava returns to Mathura (not Dwaraka) . Done. Plain and Simple.
The creatives have sucessfully made it into a intellect Vs Bhakti battle which was certainly not the case. If it were so, Krishna's exposition of Hamsa Gita to Uddhava, would not be relevant