Signal boss warns app will exit Australia if forced to hand over users’ encrypted messages
(www.theaustralian.com.au)
The raspi still needs to be out of the country for it to work how you want it to. If you have the raspi in the same area then the data is still vulnerable. They may block vpn providers, but they just can't block wireshark connecting to a off shore server because they would shutdown alot of methods, buissnesses use to transfer data. Well they could but it be some next level stupid.