Removing the spotlight when people still coming into the waiting room

[BuckleyGirl]

Hi! Practical question for a Zoom call with around 500 people in. 

We use a countdown timer that I spotlight for the 10-minute countdown. When the countdown ends, I need to remove the spotlight for the already spotlighted keynote speaker to be up on screen alone. 

As the countdown ends, people are still waiting to be admitted from the waiting room, so the participants' list jumps around constantly, even when popped out.

Is there a way to keep the timer where I need it so I can remove the spotlight? Or am missing something really simple? 

Thanks so much! I really need to get this figured out...