Tableau Desktop to Redshift

Based on my understanding of the question its just an issue caused by changing of IP when switching to VPN in home network. For this use case the customer can possibly consider the below workarounds. Also

1. Instead of installing Tableau desktop on user desktop it can be installed on a Virtual Machine or a EC2 instance and they use that instance for connection to DB.

2. Rather than opening a single user IP you can allow the user IP and also VPN IP range for the company. This is little less secure as it opens the database to any user within the organization.