If it was me I would refridgerate it as soon as I turned it off. I work in an aged care facility in the kitchen and currently studying a cert 3 in hospitality. We have just done our food safety component which basically says any meat must be cooked to its internal temp maximum and you then need to have it cooled to certain temps in the following six hours. So having said all that I would let it rest for 10 mins maximum then slice and place on a large plate- the more surface area the quicker it will cool-less likely that bacteria will grow.

Hope that makes sense.