I got some additional intel today. Both from a Jeep dealer, and from some posts on other boards. Don't know that any of this is accurate but just putting it out there.
1) When a dealer honors affiliates pricing, they get reimbursed by Stellantis but not for the full difference between MSRP and 1% under invoice--they get more than 1%, but less than the full spread.
2) Stellantis apparently audited a high volume dealer, and they had to refund Stellantis a fair amount of money (~250K) for violations of the affiliates program--in this case, it sounds like it was selling for even less than 1% under sticker. (This would explain why dealers offering a better deal don't care about doing the affiliates thing--it could come back to bite them.)