I found a strong corroborating transmission for al-Alhani: al-Walid ibn al-Walid said, “Ibn Thawban narrated to us from Yahya ibn al-Harith, from al-Qasim, with the same report.” Al-Tabarani narrated it (8/212/7749) through two chains from him.
I say: This is a good chain of transmission. Al-Walid ibn al-Walid was al-Ansi al-Qalansi of Damascus. Ibn Abi Hatim (4/2/19) reported from his father: “He is truthful; there is no problem with his hadith, and his hadith is authentic.” The narrators above him are well known among the narrators of Tahdhib, though some criticism has been made of some of them.
There is also corroboration for the revelation of the verse in the hadith of Ibn Masud: he was asked about this verse: “And among people are those who purchase distracting speech to lead astray from the way of Allah without knowledge.” He replied: “It is singing, by Him besides Whom none has the right to be worshipped,” repeating it three times.
Ibn Jarir narrated it, as did Ibn Abi Shaybah in al-Musannaf (6/309), al-Hakim (2/411), and al-Bayhaqi (10/223). Al-Hakim said: “Its chain of transmission is authentic.” Al-Dhahabi agreed with him, and it is as they said.
Similar to it is the report recorded by Ibn Abi Shaybah (6/310), al-Bukhari in al-Adab al-Mufrad (1265), Ibn Jarir (21/4), Ibn Abi al-Dunya (folio 4/1–2), and al-Bayhaqi (10/221), through Mansur ibn Abi al-Aswad, from Ata ibn al-Saib, from Said ibn Jubayr, from Ibn Abbas regarding this verse: “Those who purchase distracting speech.” He said: “It was revealed concerning singing and the like.”
I say: Its narrators are reliable, so its chain of transmission would be authentic were it not that Ibn al-Saib had become confused in his later years. Thus, it is at least a good corroborating report.