That's exactly exactly what i mean, even tho it was your gateway ip, you still fell for it. Which proves that the IPs rizen saw were not actually the real player IPs. Anyone with a few hours in networking would immediately recognise the IP, yet you didn't, which proves those "tutorials" are fake.
TL;DR
It's IMPOSSIBLE to get someones IP address by simply sending them a message on steam, or voice calling them in the same platform (or even discord, Skype, teamspeak) without actually gaining privileged access to any of the platforms.
Just do yourself a favor and search peer-to-peer connection.
And no, i would never use my rights to leak any IPs. At max they are used to block schums.