So the thumb button on my logitech mouse sends Ctrl-Alt-Tab, I mapped this in system settings to this dbus action:

app: org.kde.kglobalaccel
remote object: /component/kwin
function: invokeShortcut
arguments: "ExposeAll"

This works fine to show the "Present Windows" screen, but I would like it to cancel and return to the previous view when I press the button again, is there a simple way to do this?

You can customize hot key in system settings → desktop effects → present windows options
I changed it to meta+tab

There is also Present Windows Button
https://store.kde.org/p/1181039/

That works perfectly, and it cancels the effect when I press the button again, thank you very much!