What is the ruling on taking money in exchange for recruiting workers for a company, and does the ruling differ if the workers initiate the payment?

This person is an agent for the employer, not a broker, and it is not permissible for him to take money from workers in exchange for a visa unless the employer gives permission, because he works for the employer and receives a wage from him. As for the employer himself taking money in exchange for a visa, this falls under the price of influence (thaman al-jah), which is a matter of scholarly disagreement. If the workers give the agent money as a gift, there is no harm in him accepting it, provided that this does not affect the employer's interest.