The Emoluments clause of our Constitution prohibits any federal officer, including the President, from accepting anything of value from a foreign power, lest they become corrupted by it, without the permission of Congress. The Trump Organization is solely owned by Donald Trump. He put it in a revocable trust to be run by his children while in office, but he still owns it.
So our Congress is upset because he didn't ask permission.
But what's he actually accepted from HMG?
The way the scheme works, HM Revenue and Customs know what The Trump Organisation's employees earn every week/month, because they receive from the golf courses' finance offices the employees' tax and National Insurance contributions under the Pay As You Earn scheme.
So, for furloughed employees, HMRC reverse the process and pay the emergency support to The Trump Organisation, who then pay it to the employees via their regular payroll run.
The funds pass through The Trump Organisation's bank accounts, that's all, and I don't see that as accepting something of value, any more than it is when an employee who has paid too much tax under PAYE receives a refund via his or her paycheck.
It's not like foreign governments booking suites at his Washington hotel to put money in his pockets.