I released a Google calendar, task, and reminder integration:
It will allow you to automate things based on these Google items. I have been playing with making reminders more dynamic by parsing the reminder text to then turn on or off switches mentioned within the reminder to then match up to a list of devices defined within the trigger child app.
I live in an Alexa household but if you say Google remind me in 1.5 hours to turn off the heater does it create a Google Reminder you can see in your Google account? Does the due date set to 1.5 hours from now? I ask because this app and new enhancement might work well for you.
But you would have to turn it on first and then setup the reminder to turn it off. My app would pick that up and turn it off along with marking the reminder completed.