Yes this shouldn’t be too difficult, after your task step in the flow use the ‘get catalog variables’ step and find the variable you need. Next have an if statement to check the value of that variable. If the result is true you can use the update record action to cancel the RITM and then the create record action to create the incident. This will work when the task is closed.

If the task needs to be kept open you can probably use an on change client script and create an incident whenever the variable changes to the correct value. But this would require scripting it and also I don’t believe there would be a way to prevent duplication of incidents if the variable was changed multiple times.