Ineos ought to stage an invitational on the same course as Eliud ran his non record eligible sub 2 but with record legal conditions. Invite 10 to 12 of the top marathoners. Either provide some pacers or have the invitees bring along one personal pacer. Time bonuses for sub 2, sub 2:01, sub 2:02 etc. Maybe even bonuses at intermediate points during the race.
They’ll probably need to put down cones in the turnabouts to prevent anyone cutting the course.