I stand corrected and you and the original poster are correct. Rebates from Broker to Buyer are non taxable income.
https://www.inman.com/2011/05/06/tax-practices-real-estate-commissions-rebates/
http://timelineres.blogspot.com/2011/04/while-rebates-from-real-estate-agents.html
Thank you.
My understanding is, if the rebate is done through escrow, (1) the actual amount seller paid to Buyers broker (factoring if Broker gave a rebate to Buyer) is what the Seller reports to the IRS and the rebate portion is treated as a reduction to purchase cost. So I agree with what you posted on...