Radha dasya is their meditation – service to Srimati Radharani. They have understood the point that we can try to please Krsna directly, but who can please Krsna more than Radharani?
No one can please Krsna as much as she can. So if we really want to please Krsna, then give him Radharani. Therefore, such devotees are all pushing Radharani forward – assisting Srimati Radharani in the service of Krsna.
So that is the line of Sri Caitanya Mahaprabhu : gopī-bhartuḥ pada-kamalayor dāsa-dāsānudāsaḥ (Caitanya Caritamrta Madhya 13.80) So we are the servant of the servant of the servant, and prompting the other servant forward, not like, you know, elbow here, elbow there, and pushing ourselves in front. No, we say, “You go first. Krsna surely will be pleased to see you, and especially Radharani.”
So this is the spirit of transcendental knowledge.