Direct messages as a thread, not separate

I run training sessions using Zoom meetings.

I used to ask trainees to send direct messages to answer some questions to test their knowledge and I would see all their answers as part of the main chat thread.

Recently direct messages now all pop out into separate conversations, meaning I need to click on each one separately to see answers. I've therefore had to ask trainees not to use direct messages as with 10 trainees it means I can no longer just quickly glance to see whether everyone has the correct answer without them being able to copy answers from others.

Is it possible to toggle this option on and off so I can choose whether to have a single thread with all messages in the chat or separate threads for each conversation?