Do the souls in Barzakh await our duʿās and sawāb from Dunyā?

Assalamu alaikum, I found an ebook called “Our Dear Deceased and Ēṣāl-e-Ṣawāb...” and it made me a bit unsure about a few things, so I wanted to ask if what's written there is reliable. The book shares stories like these: - Hadrat Hammad reportedly slept in a graveyard in Makkah and dreamed that the deceased were gathered in groups. When he asked if Qiyāmah had come, they said no, and that one of their brothers had recited Sūrah Ikhlās and sent its reward to them, and they had been sharing that reward among themselves for years. (Noor us Sudoor Fi Sharhil Quboor) - It also says when family give charity for a dead person, Jibrīl (ʿalayhi s-salām) brings the reward on a tray to the grave, and the deceased feel happy and relieved while others nearby are saddened for not receiving rewards. (Tafseer-e-Mazhari) The ebook is online for context, but I won’t link it here. My real question: we believe in Allah’s mercy and that duʿāʾ and sending sawāb can benefit the dead. But do souls in the barzakh actually wait for or scramble for duʿās and sawāb from the dunya in this literal way? Are these kinds of narrations authentic, or are they more pious tales to encourage good deeds? Is there clear evidence from the Qurʾān or ṣaḥīḥ ḥadīth that the deceased depend on the living in this exact way? I fully support making duʿāʾ and giving charity for the deceased - I just want to know what’s established Islamically versus what might be weak reports or later interpretations. Would appreciate clarification and any scholarly sources or references. JazakAllahu khair.