Didn't see mentioned here that the SSD may have an invalid partition table, which could explain the difficulties of accessing it. The output from gdisk indicating 0 sectors and bytes suggests a severe issue with the disk's partitioning. Check this guide on how to fix invalid partition table...
You make some excellent points about the advantages of messaging apps like Telegram and Signal over traditional SMS, especially when it comes to international travel and privacy considerations.
Verify that your DNS server's configuration is correct. Ensure that you have properly configured forwarders or root hints to resolve external domain names like google.com. You can check your DNS configuration files for any errors.