The Lord granted the Gopikas moksha. Why did He do so? Did they perform karma yoga, jnana yoga or bhakti yoga? It may be argued that they grazed and looked after cows, which was their duty, and so they may be said to have resorted to karma yoga.
That would have been a valid argument, if they had looked after the cows that had stopped yielding milk too. But they only took milk yielding cows to the forest, as they themselves confess in Andal’s ‘Karavaigal pin sendru’ pasuram. So here again they didn’t do their duty completely. They did go to the forest with their herds of cattle, and the forest is considered a sacred space for penance by sages. Forests like Naimisaranyam are worshipped. But the Gopikas did not go to the forest to do penance. So they cannot be said to have gone to the forest in a spirit of renunciation, said M.A. Venkatakrishnan, in a discourse.
In fact, the Gopikas say that they went to the forest and ate well. They might even have eaten while walking behind the cows.
There are elaborate rules about how one should eat. One must face East, and eat sitting down. To eat standing or while on the move is not allowed by the Sastras. So the Gopikas were not acting in accordance with the rules even in this matter of consuming food. So the Lord could not grant them moksha for doing karma yoga.
As for jnana yoga, they tell the Lord in Andal’s verse that they have no jnana. Bhakti yoga is a higher level of jnana yoga. So the Gopikas could not have resorted to bhakti yoga either. But the Gopikas, while expressing their love for the One who lacked nothing, acknowledged their own unworthiness, and this was what got them moksha. Admitting our unworthiness and helplessness is a prerequisite for moksha.