In the absence of access to sessionStorage, I revisited your original idea and came up with the following. It's a very simple example, but will hopefully be useful.
It works by setting the value of a global variable when initially navigating away from the home page. When loading the page, you can check to see if that variable is defined and navigate the user back to the home page, if necessary, using utils.openApp.
Do you think that is sufficient for your use case? If you have any additional questions, it would be great to have you join one of our scheduled Office Hours! Note that we won't be meeting this Thursday, but resume the normal schedule next week. 