guys, i've figured it out. he has a really good cube, and he turns really fast with it. i've seen these before, like, 1/1000 storebought cubes are actually completely godly. they can cut corners really well and almost never lock up, and turn faster than an f-2. you just have to get really lucky! i recommend he doesn't waste money buying a diy at this point.
also, for the 10s first two layers thing, some people just have really, really fast reflexes. for some of these people, it's actually faster to look for one piece at a time because their reaction time is so crazy insane. this is also very rare, which is why you see so few people compete with layer by layer instead of slotting pairs. i think if OP were to learn 2 look last layer he could start setting some really amazing times. can't wait to see him in competition.