Not sure where I did wrong but I'm not able to run it properly.
I just installed it via tampermoneky, the script is running and enabled. As for visiting
bitlist.co website and completeing the 2-second anti-bot verification, what do you mean by that? I did visited the site but there wasn't any verification or anything. I might be missing something as I haven't read all the replies here. The point is, nothing happened. Guys, a little help!

If you have installed version 0.15.2, you do not need to visit the bitlist.co website.
In previous versions, I used different endpoints to obtain data from bitlist, but Anubis was present on bitlist and blocked requests made by bots. To get around this problem, you first had to visit the bitlist website, which would then whitelist your IP address.
Now I have a worker with the new bitlist APIs, and there is no longer any need to do this. The script works without having to visit bitlist first.
That was the crux of the problem, but it has now been fixed.
I think I was on the latest version. Yes 0.15.2 one.
Ok here is the update (a little late I guess).
When I first installed it for the first time, nothing happened as I said earlier. So I visited bitlist, waited and still nothing. Later, after a couple of hours, it worked, on it's own. Didn't touch anything. Maybe it was a internet thing or cache related issue. The point is the ratings are showing now. Now, what I observed is that the rating doesn't appear instantly. When scrolling through a page of multiple users, it takes 1-2 seconds delays before slowly updating the rating one by one. Could it be because I'm using it for the first time?

edit: I didn't read your previous comment about the intentional slowness. So i guess that explains it. All sorted.