This is certainly impressive, but whenever IMO is brought up, a caveat should be put out: medals are awarded to 50% of the participants (high school students), with 1:2:3 ratio between gold, silver and bronze. That puts all gold and silver medalists among the top 25% of the participants.
That means that "AI solves IMO problems better than 75% of the students", which is probably even more impressive.
But, "minutes for one problem and up to 3 days for each remaining problem" means that this is unfortunately not a true representation either. If these students were given up to 15 days (5 problems at "up to 3 days each") instead of 9h, there would probably be more of them that match or beat this score too.
It really sounds like AI solved only a single problem in the 9h students get, so it certainly would not be even close to the medals. What's the need to taint the impressive result with apples-to-oranges comparison?
Why not be more objective and report that it took longer but was able to solve X% of problems (or scored X out of N points)?