Is it permissible to place papers containing requests and needs in a niche in the Dome of the Rock Mosque, which is said to have the scent of the Messenger (peace be upon him), or is this an imitation of the Jews?

There is no evidence for the claims concerning the Dome of the Rock. The Messenger (peace and blessings of Allah be upon him) is not there; rather, he is in his grave in Medina. Seeking the fulfillment of needs from the dead is polytheism (shirk) from which one must repent. Students of knowledge should educate communities about the prohibition of asking the dead and seeking their aid.