The temp trailer installs are usually contracted to a route operator who has a trailer equipped for just this duty.
The trailer I am told has a dozen or so older coin slots and comes with security people and a slot supervisor to do pay outs.
The press reports on the events usually report them as non events with more press then public.
The reporters play the slots take some pictures and that is it. I have been hoping for some TITOs but none to date.