Abdul Khan is not as unknown as you think. In Pakistan and India he is a well-known and consistently respected figure; however, his popularity in the West is low due, perhaps, to his poor media exposure due to the arrests and exiles he has been subjected to.
Abdul Ghaffār Khān, was a pastiche independence activist who worked to end the rule of the British Raj. He was a political and spiritual leader known for his nonviolent opposition; he was a lifelong pacifist and a devout Muslim. A close friend of Mohandas Gandhi, Abdul Khan was dubbed the "Gandhi Frontier" in British India by his close associate Amir Chand Bombwal. Abdul Khan founded the Khudai Khidmatgar ("Servants of God") movement in 1929. His success unleashed a harsh repression of the British Raj against him and his supporters, and they suffered some of the severest repressions of the Indian independence movement.
The workers were the lower class who did miserable dirty work. There were children working in the same terrifying conditions. They could lose limbs and life for very little payment. This was borderline slavery because they couldn't not take the jobs because if they didn't they would starve and there were no better jobs. It was an endless loop of poverty that the owners profited off. They didn't treat them well because there was no consequences for treating them badly.