Since you don't need any video evidence, isn't it very easy to cheat and create a fictional time in photoshop? Or maybe there's some way to look up on mineplex, whether or not that time actually happened?

well, we recommend video evidence but its not required. people that we trust can use screenshots. if we dont know who the person is submitting the run and they submit a time, we usually put this in the rejectment reason, " Skill Verification Required from Moderators". this means the moderators will expect a video from the person submitting the run to see if your legit or not.

edit: we also have people who can detect photoshop within a screenshot.

Have you contacted mineplex? Maybe they keep data on people's high scores. I know they'd do something like that on the hive atleast.

We acknowledge that it's easy enough to fake a screenshot; using videos is always welcome. (Even for well-known players!) Unfortunately, Mineplex puts no developers on Speed Builders; I have bug reports dating to the game's release which would still be hanging if not for their forum move.

Besides, the problem with Mineplex keeping people's high scores is that some hackers have appeared during the game's history.

Dolphie explained it pretty well, but if you preform well in game with other good players or show off a run in singleplayer that is similar or better than the wr of that build than there is a high likelihood you will get accepted as well. Also a lot of players gloss over inconsistencies with times and builds when photoshopping that are pretty easy to spot if someone looks over it.