Is it possible to pause an automation in a guest mode? If not, it may be a good idea to add this as a new feature.
Can you add a condition and select all the other modes except for guest mode in the automation? That way when in guest mode, the automation would not run.
It’s time consuming, but doing what @milandjurovic71 suggested on all your automations/smartapps is the best way to do it. That way when you switch the mode to guest nothing runs. You can also use a virtual switch or something as well (I use the guest mode).