OP, if you look at the pictures, you can see that tire wear on the shoulder is almost down to the base rubber (or "bald").
Regardless of all of that...when you get down to brass tacks, you have a 50,000 mile tire that you (or your friend) received 27,000 miles of service from. Michelin is offering you a new tire at right at half the cost of a new one, which is how pro-rated tire warranties work. The "free replacement" period of almost every tire warranty ends at 12 months or 2/32" of tread wear. It doesn't matter if this tire is a Michelin, a Goodyear, a Bridgestone, or a Mastercraft...if that tire needs replacing due to a defect after you've gotten half of the life out of it, the manufacturer will offer you half off a new tire (which Michelin did here).
I don't know if you expected a free replacement here. If so, I don't think you'll find satisfaction with any tire warranty. That's just not how they work.
Either way, I do sincerely believe, based on the pictures and based on your description of the tires having 6/32" of tread somewhere on them, that the car has a severe alignment problem or the tires were severely under-inflated. If you regularly checked inflation and it was good, then there has to be a mechanical problem with the car for the tires to wear like that.