I'd disagree on not knowing since all courses have putting greens, and the good courses have putting greens that reflect the speed of the greens on the course. There you can practice and get an idea for the speed before playing.
But there you are playing solo . Either choosing a green speed or playing the default of your tier .
In Stroke Play , Alt Shot , Match Play . The green speed is the speed of the highest tier in the match .I think these should all be random green speeds .
In coin games . Every match is a new random green speed . With no regard to the tiers playing .
Major Tournaments are all Champ green speeds .