Legally, everytime they played DS songs, MK receives money from that concerts because of the copyright of his songs. They have not to share the ticket money with him, as legally, just the copyright is enough.
Another different thing is if they reached an agreement that establish that, but ticket sales are for the performers, and then they have to pay, from that money, the copyright shares that belong to MK, thats the same to every tribute band around the globe.