What browser? I don’t have a TikTok account but I tried to connect to Italy and used incognito mode in the Brave browser. At least the login page for TikTok opened fine for me offering to create the account. Perhaps your browser or something else on your device gives away your location.
Not a Tik Tok user so I can’t check it, but I followed the instructions here for getting around another geolocation system through your browsers latitude and longitude info. You have to use the Dev Tools, it only works for one browser tab, and you have to refresh every couple of hours… but it works on a browser. You would probably have to do this, then create a new account “from” the country you were pretending to be in, and I doubt you’ll ever get it back up on your phone because most services have VPN detection software. You could try using an “obfuscated” VPN through Nord’s specialty servers, but thats hit or miss.
Browsers only share location information if you opt in to doing so for a specific site, which I have not for TikTok.
not true, depending on the browser, most default to share location
Do you have a source on that? Here’s the relevant Chrome help page saying location sharing is opt-in, and it tracks with what I’ve experienced: https://support.google.com/chrome/answer/142065
I can’t speak to other browsers but I’d be surprised if they didn’t behave similarly. My gut says giving away your location by default is a potential security issue, or at least something the browser doesn’t have any incentive to do.
“Location” in this sense being distinct from IP address, which is necessarily revealed by any web interaction and can be traced back to a rough location. But masking your IP is the whole point of VPNs of course 
Look up ,“WebRTC leak”. It’s often revealed by your DNS access settings, not your browser.
I just used a couple of WebRTC leak tests using NordVPN and they both said there’s no leak, unless I turn on audio or camera permissions for the site in which case it does leak. But I would never have any reason to turn on audio or camera permissions when visiting TikTok on a laptop.
Didn’t Tiktok ask for camera permissions, even in the desktop version?
Idk if it ever did, but when I look now it does not have camera or microphone permissions.