Will WebWork take screenshots of all monitors if there are several?

You can enable your workspace members to select which monitors WebWork should track.

Go to Settings > Tracker > Desktop Software Tab and enable Allow workspace members to select which monitors to track. 

However, if this setting is off, the tracker will track all monitors by default.

How to select monitors?

To adjust monitor settings, open the Desktop Application and navigate to Settings. In the Monitors section, you can select the number of monitors you want to capture.

Now WebWork will track the selected monitors.