This case is about a structure many business groups use in some form: one entity trades, another entity employs staff, and money moves around the group to make payroll happen. That can be legitimate, but it needs documents and behaviour that match the intended structure.
The Court did not simply say the fairest outcome for employees decides who the employer is. It looked at objective legal principles. On the evidence, Brownlen was likely operating as agent for an undisclosed principal, Apollo Kitchens, for the relevant employees. The liquidators were given a direction that they were justified in treating those people as Apollo Kitchens employees for the winding up.
For businesses, the point is not to avoid group structures. The point is to make them real. Employment contracts, service agreements, payroll funding, workers compensation, HR policies and internal accounting should all tell the same story.