Honestly, this sounds like a job for Tor. Install Orbot, possibly enable a bridge, and you should be good to go. Onion Browser is recommended for use with Tor, but Safari will work just fine.
I have never tried calling over Tor, but I have never had an issue with the speed before (although it is inherently slower than a VPN).
Tor Bridge Types
- obfs4 makes your traffic appear "random"
- snowflake disguises your traffic as VoIP
- meek-azure makes it look like you're connecting to Microsoft services
- meek-amazon makes it look like you're connecting to AWS
- meek-google makes it look like you're connecting to Google