I don’t think the essay will help because the ECs are not telling the story of a highly motivated future engineer.
M has a high bar for COE applicants. It looks like this student has ability and opportunity to make the effort needed to clear the bar, but is focused on other interests/priorities. That is fine, but just it doesn’t show the level of achievement, motivation, or interest in math, science, or engineering that M tends to look for.
This student clearly has the ability to become an outstanding engineer, but M is probably going to have candidates who have done a better job of conveying that. If this student doesn’t make an effort to bolster their application, they are likely to be rejected, and that could be a win/win. It is entirely possible that this applicant will be more successful where the competition is just slightly less accomplished and determined.