I am new to speedrunning in general and therefore also to doing it in this game, but I have a few questions about the leaderboards in-game.

Are the in-game boards a reliable source or should I ignore them and just use the ones here.

I'm asking this, because the in-game boards have more entries. Which is not surprising, since everyone who played the game has an entry, but the times of the entries make me wonder.

There is an entry with about 6 min. which only has 1% completition, that can't be a legit run, can it? I mean I saw the race between Grimelios and Ankamius (That actually brought me to this awesome game in the first place, thanks for that if you two are reading this.) and they needed about 6 min. or so just for mount horu and they were fast. seems kinda impossible to make a 6 min. run without cheating completely.

Another entry states to have 100% in about 16 min. which seems impossible by legit measures or am I mistaking there.

The other top entries have nearly the same (incredibly fast) time without deaths. I don't want to accuse anyone of anything, but is there a bot existing and they just didn't start it at exactly the same time?

To summarize my question: Are the top times on the in-game leaderboard in any way trustworthy or should I just look on the leaderboards here and don't even look at the ones in-game?