What determines which VIP host will be participating during the stream

[Winning1850]

What determines which VIP host will be participating during the stream? Just curious i got switched to @JovanWho is a boss VIP host but unfortunately he only picked rooms 1 time within the last 3 streams. I already know the odds of the stars aligning to even give me a chance to get picked are slim but since i have so much time on my hands i figured id ask hehe