According to Ramakrishna Paramahamsa and Swami Vivekananda, which is more important in attaining moksha- Bhakti or Jnana?
They're equally important.
I'm here quoting some relevant quotes of Swami Vivekananda from The Complete Works of Swami Vivekananda/Volume 3/Bhakti-Yoga/Definition of Bhakti:
There is not really so much difference between knowledge (Jnana) and love (Bhakti) as people sometimes imagine. We shall see, as we go on, that in the end they converge and meet at the same point. So also is it with Râja-Yoga, which when pursued as a means to attain liberation, and not (as unfortunately it frequently becomes in the hands of charlatans and mystery-mongers) as an instrument to hoodwink the unwary, leads us also to the same goal.
It is not given to all of us to be harmonious in the building up of our characters in this life: yet we know that that character is of the noblest type in which all these three — knowledge and love and Yoga — are harmoniously fused. Three things are necessary for a bird to fly — the two wings and the tail as a rudder for steering. Jnana (Knowledge) is the one wing, Bhakti (Love) is the other, and Yoga is the tail that keeps up the balance.
There is a little difference in opinion between the teachers of knowledge and those of love, though both admit the power of Bhakti. The Jnanis hold Bhakti to be an instrument of liberation, the Bhaktas look upon it both as the instrument and the thing to be attained. To my mind this is a distinction without much difference. In fact, Bhakti, when used as an instrument, really means a lower form of worship, and the higher form becomes inseparable from the lower form of realisation at a later stage. Each seems to lay a great stress upon his own peculiar method of worship, forgetting that with perfect love true knowledge is bound to come even unsought, and that from perfect knowledge true love is inseparable.
Btw, it is often interpreted that "Bhakti is an extreme love towards Brahman" & "Jnana is the Brahman itself"
Note: “The question: According to Ramakrishna Paramahamsa and Swami Vivekananda, which is more important in attaining moksha- Bhakti or Jnana?” is licensed by Stack Exchange Inc (https://hinduism.stackexchange.com/); user contributions licensed under CC BY-SA.