Strange problem with Rossignol bindings

I'm posting to see if anyone else has had a problem with the sole thickness of full tilt boots causing pre-release with rossi bindings.
I'll explain my problem a little bit more elaborately...

At the end of last season I broke my old Armada Thalls and ended up getting a new pair of Bdogs and having Rossi Axial3 120s mounted on them. I'm a pretty skinny guy and I had a pair of Rossi Axial (first generation) 120s on my Thalls also. With that set up, I never had any issues with pre-release, so I feel the 12 DIN binding works well for me.

I had the BDogs mounted by a reliable shop, had them properly tested, and got up to the hill to test them out. The first thing I wanted to do? A nice nose butter 3 off a cat track. Immediately upon putting pressure on my nose, I released from the heel of the binding on both skis. The rest of the day was a complete wash, with my heels releasing on every switch landing and with any good amount of pressure over the nose of my skis.
My first suspicion was just that whoever adjusted the binding misread a DIN chart or something, but no, the bindings were properly adjusted for my height, weight, and skiing needs.

I took the BDogs back to the shop and told them about my problem. They tested the release values over and over and over and over and the bindings were releasing consistently and perfectly within the expected values for my DIN. They rechecked the mounting, and everything was fine.
The shop ended up taking the skis for about two weeks to continue to work on them and look for a solution. They called the Rossi rep to talk about the problem and see if they had ever heard of this before and if there was a solution.

When I came back to finally pick up my skis, they had an explanation but no solution. The shop owner asked me what kind of boots I had. I told him I had Full Tilts and he said there was my problem. All jokes about Full Tilts being poorly made boots aside, he said that the sole on Full Tilts was the thinnest in the market, and that's why the bindings were releasing.
He said that they have this pre-release problem on both the Axial and the FKS with Full Tilts. I found this really really really hard to believe given how many people ride Full Tilt and FKS setups and have no problems. Additionally, I rode my first-gen Axials with my Full Tilts, and I never once had a problem with releasing from the heels.
The problem with just cranking down the heel is that it would fuck up when the binding normally releases when I'm not flexing into the nose. He said he wouldn't recommend just cranking down the heel, but that it might help calm the problem down, but not fix it.

I tried to contact Rossignol directly, and they never got back to me.

So I'm looking to the bindings wizards of newschoolers to help me out here!
Has anyone else seen this before?
If so, what did you do to fix it?
Am I actually just straight up fucked?