Not sure what B2B is, but I digress. OK, so Mazda will take out your driver seat, and at your insistence, maybe the front passenger seat also. They will remove the leatherette covering from the seat bottom and install it back onto a new seat bottom made of the same mateial that failed initially, seems to be failing for most owners, and will certainly fail again since it's constructed of the same material as your current seat bottom. Unless the foam moving inside (as you stated) is due to the seat manufacturer covering an already torn bolster with its leatherette covering, then you will again experience the same or near-same failure as before, and as others here are already experiencing.
What is there to gain. I'll tell you. The leatherette covering will be re-used and may or may not fit as well (or as badly) as before the seat bottom replacement, and the trim panels around the seat bottom will start popping off from your body weight because they never secure as strongly and tightly as they did before disassembly. The locking points of the trim pieces are cheap plastic and once pried apart will only stay together if there's no weight pressing down on them, like the weight of your body as you sit in the car to drive it.
So, at best, your seats will be taken apart and replaced with the same faulty seat bottom and bolster material that will ultimately fail again unless the bolster was damaged in a one-time freak incident at the seat manufacturer level. You will hope the leatherette covering will fit nicely again and that the removal and re-installation of the seat does not cost you rocker panel sheet metal/paint damage if the tech is not astutely careful, and you will again have to petition Mazda for replacements, this time for the seat surround trims because they will now be popping off under load, and later for more new seat cushion because they will surely fail again. I know this because my previous Mazda had the same type of seat trim issue when the seat bottom was disassembled to satisfy a recall, and more recently, the exact same work was done to my Infiniti and the seat surround trims starting popping apart on it also. Not only that, but the leather cover now fits like poop and they now claim it's normal wear (and they refuse to make good), because Infiniti is as crappy of a warranty administrator as was my Hyundai before it was lemon law repurchased. You've had good luck, it seems, with Mazda. Maybe you know somebody, maybe you don't. Either way, at some point, they will see that your car is racking up quite a bit of warranty administration cash (if I recall your trans and clutch assembly was replaced with new units) even though non of the warranty claims are your fault. Mazda is no better at backing their cars than anybody else (except Lexus as a manufacturer-not their dealers), and they will eventually start to buck as the invoices start to stack up and the profit of selling this unit diminishes.
Again, none of this is your fault, and we are all apparently stuck with Skyactiv light body parts (a.k.a. feather light seats, bumper covers, etc) that have no resilience over time and are therefore Skyactiv=cheap.
I don't know. Maybe I should have purchased the 9th gen Accord v6 Touring for a few dollars more and some handling ability less. But, forgive me for saying, in your case, the seat replacement(s) in your case may not solve your troubles long, and may actually be putting you in worse off condition down the road than you are now. Please don't think I'm saying ANY of this is your fault, but I'm giving you the scenario that will very likely unfold in your founded desire to have your car made whole, which is what you and all of us deserve with any and all warranty concerns.
Good luck, and please don't thigonk I'm hating by giving you my experience with car seat issues and the automotive warranty administration across several manufacturers, including North American Mazda.