As far as I know other than the paraphrasing/vision of Sri Krsnadasa Kaviraja, they have attributed 10 verses to him, siksastakam and two others—aham vipra na ca nara patir . . . , and srutam api upanisadam dure hari kathamrtat. . . . . When they site them they refer to them as the words of Bhagavan.
This I found in the thread about Guru-Tattva. I could find the aham vipra-verse in Cc. The other one was more difficult, but then I found that it was in Srila Rupa Goswamis Padyavali. But there the sloka is attributed to Srila Vyasadeva. Does anyone here know more?