Ilia can make group 3 by being top three at Nats.
Ilia will probably be in group 3, but the USFS document clearly says they will put skaters in the same group in order of achievements or scores. The possibility is grater for Jason to be ranked higher in the particular group (3rd) than Ilia.
Ilia has a shot, but it will be very difficult for him to be above Jason. A 275 domestic score at almost your best won't do it.
That is if Jason's injury will heal completely in the next weeks, but even if it's not, at Nationals Jason is capable of defeating Ilia by a large margin of points even with all of Ilia's quads and Jason having an iffy quad.
Jason needs to bomb majorly in the rest of the season for Ilia to even have a chance IMO.
I'm sure they are doing everything in Toronto to keep Jason as healthy as possible and healed soon. It would not be the first time he overcomes serious injury and comes back to earn PBs and medals.
Worryingly, Jason even said they changed the layout of the 3F from the short to replace it with a 4S in the future. He's fine without that and I hope he's not pushing himself too much because very likely he will be on the team.
I've been closely observing Jason Brown for several years and he's not the skater he was four years ago. He demonstrated at Worlds 2021 that he has very strong nerves now and does well under pressure.
US already has two great skaters with high technical skills, they should be more than happy to give a spot to a skater who is a champion at PCS and the praise of almost everyone when it comes to skating skills and thus show they have such complete talent in their country. A skater who can well be top 6 at the Olympics and is often above their Russian "rivals" oftentimes on pure PCS and beautiful skating that the audiences love.
It just seems the most logical to me if Jason will get good scores the rest of the season.