Okay, another thing about the theory.
So, this is the score graph from an hour ago, when I posted the above update.
View attachment 6751070
This is the screenshot I just took.
View attachment 6751074
Chris has earned 537 points within the last hour. Something especially interesting, considering it is (at the time of me taking this screenshot) 11 AM for Chris, almost the time Chris would normally wake up at.
Which means he has either woken up an hour early and instantly started spamming Duolingo, or he is in a different timezone.
From what I have noticed, he also does Duolingo lessons later in the day, usually after I have already gone to sleep, which does line up with the current time in Finland (6 PM)