The problem with this scenario is that you are relying on Network Address Translation (NAT) to hide your physical location.
This assumes that IP Address = Physical Location.
Large IP address sets like 34. *. *. * are owned by top tier providers, who usually sell an address range like 34. 138. *. * to local providers, who assign ranges like 34. 138. 17. * to a business.
Since there are limited IP Addresses most businesses have an internal network IP Address assigned to their employees separate from any Internet public IP addresses. Then the business keeps track of what internal IP address did which request out to the Internet and routes the response to the internal IP address.
This is called Network Address Translation or NAT for short.
Your friend's work most likely has a log of who logged in over the LAN VPN connection. Therefore the government can ask or serve a warrant to your friend's company to see who was on at a specific time. The trail will lead back to your friend. And because his work likely knows where he lives. It won't be hard to find you.
Also depending on the capabilities of the government, they might have physical address location capabilities that don't require the cooperation of your friend's company.
In order to protect yourself from government spying, try a network anonymizer like Tor ( https://www.torproject.org/projects/torbrowser.html.en ).