It's not possible to send a business to a yard, so this is probably a play on the expression "breaker's yard": a scrap yard; the place that old cars are taken to for breaking up. Presumably these brokers (definition below) tried to find buyers for the ailing businesses.
one who acts as an intermediary in arranging marriages, negotiating agreements, etc.:
A 'breaker's yard' is a yard where old cars, machinery etc. is sent for scrapping. This would seem to fit this context but the author uses 'broker's yard'. I don't know if this is a play on the idea of broker/breaker where a broker is a a business engaged in the dismantling of businesses to strip their assets for sale.
PS. I see sound shift has said almost the same thing.