The answer is he sent in strikebreakers.
Andrew Carnegie is not known for raising worker wages in response to labor disputes. In fact, during the late 19th century, many industrialists, including Carnegie, were more focused on maximizing profits and maintaining control over their operations, often at the expense of workers' demands for higher wages and better working conditions.
Carnegie did not join the protestors. As a leading industrialist, his interests were aligned with maintaining production and profitability, rather than supporting labor movements that could disrupt his business operations.
Carnegie's response to labor disputes, particularly during the infamous Homestead Strike of 1892, involved the use of strikebreakers. The Homestead Strike was a major industrial lockout and strike at the Carnegie Steel Company plant in Homestead, Pennsylvania. Carnegie's plant manager, Henry Clay Frick, hired Pinkerton agents to break the strike, leading to a violent confrontation. This event is a well-documented example of Carnegie's approach to handling labor disputes, prioritizing the continuation of production over negotiating with unions.