You need to ask in the specific game's forum, or their Discord server, or a game page moderator directly if it is unclear in the rules.
Go to this link and make a support ticket for a new game to be added, once your account is 1 week old. You will also need two contactable social media links on your profile. This is necessary because requesting a new leaderboard makes you the only board moderator at the start. Also be sure to check out the list of kinds of games that won't be accepted onto the site. @Flame_Fur
building on the prior responses, I hypothesise, although I'm by no means especially knowledgeable here, that a lot of bots insert malicious or advertising links into their profile's website link on here, and it improves that website's online traction or discoverability in some way. Certainly applies to names, a lot of the most annoying bots don't come under this category but bots might just have the same name as the target site or company improving it's digital footprint.
@MarloMartin Even though the television isn't a mainline platform for Crossy Road on their leaderboard, 11,600 would be a world record on any platform. Because of authentication you do need a full video of that run to have it on the leaderboards, but in all fairness highscores aren't really the intended focus of the website.
@socalspeedster I was about to write out that it normally takes 3 weeks for submissions to be verified, but you're submitting for King Neptune's Adventure which has no moderators. If you're happy to become the moderator you can just submit a support hub request to be added as the moderator (then you can verify your own run). You can also create your new category for the game as the game's moderator. Only game moderators can edit the categories on a leaderboard.
If you don't have any interest in moderating the board you could still do this and then remove yourself when finished, or just leave it pending in the hopes that someone else is interested in helping.
You have to moderate the game. If you do not, then you need to communicate your category idea to the community or a moderator themselves and see whether there's any possibility of it being added.
Ask for help either in the game's forum or the game's community Discord
Whilst this is a slightly older thread, I will suggest @EchoBaz that Akuretaki and ShesChardcore among others have tried to speedrun a very large number of games. Presumably, so as not to dedicate all of their time to it, many submissions (at least to games I'm involved with) don't always utilise lots of glitches or beat vast swathes of the leaderboard. However, they do both have a huge number of world records in this conquest, and might be what you're looking for.
Great changes in good time, just 2 weeks after the announcement, still time for archivals and sustaining proofs on our boards. Maybe a bug or two so far but the run identification and interface are ideal.
Pleased to see helpful practical discussion about a solution and staying 'alive' as it were, with a bigger focus on tackling tedium (automatic alternative) than making do with sticking everything on YouTube or delving straight into internet archiving, which I do think will be useful too, in lieu of a 'new-better' hosting solution, ideally much more decentralised as has been echoed above. Making efforts to communicate this to boards I'm involved with. Thanks Meta, hope everyone facing individual serious problems because of this nebulous change comes out well.
My next idea would be to ask if you've updated LiveSplit to a newer version recently? Although if you had you would've almost certainly made the connection so it's probably not that. Or have you moved the installation folder to a different hard drive and have the split files somewhere else? I did once have a similar issue having done that and moving them into the same drive fixed it bizarely.