this appears to happen only on specific accounts, I’m guessing roblox is doing some sort of A/B testing, on the image the bottom part is a functional part of the page, and the top part is the new one with Google Analytics (RobloxLaunch._GoogleAnalyticsCallBack) that doesn’t work
if you want to join on an account for which vip links don’t work, open the vip link, inspect element or press f12, paste this script into the console (don’t paste if you don’t trust the script)
var content = document.getElementsByClassName("content")[0].textContent;
content = content.slice(content.indexOf("xLaunch.Request")+55);
content = content.substring(0,content.indexOf(")")).replace(", null","");
console.log("Roblox.GameLauncher.joinPrivateGame("+content+");")
it will output a command under it like Roblox.GameLauncher.joinPrivateGame(…), paste that into another Roblox window which isn’t a vip link and it will join the server