Wealthy investors who supported Chinese billionaire Hui Ka Yan’s empire are now paying a heavy price amid growing concern the group will struggle to repay its debts. Hui had long been able to count on his poker pals to back China Evergrande Group during times of trouble, whether it was by buying stakes in his company, loading up on its bonds or not calling in debts. He broadened that circle to raise funds for his property services business in December, as well as an electric-vehicle startup in January.