Selecting which monitors in a dual setup

[kewashi]

I have dual monitor set up and it works great. However, I actually have 3 monitors - my main one is a laptop screen and two large attached monitors. When I launch zoom on big monitor #1, and share a screen, the laptop monitor is always activated as my 2nd monitor instead of big monitor #2, and it is set to full screen mode. So each time I have to mouse over to it, hit escape, and then drag it over from the tiny laptop screen to big monitor #2. 

Is there a setting to tell Zoom to use specific monitors for the dual setup when you have more than 2? I'm guessing that the laptop screen is used because it is the default 1st monitor, which I can't change. Is there a workaround?