Whatever I try, my model renders perfectly on my screen, but does not render for the other players. Also, I see the models of the other players as they used the test export function. We tried tweaking safety setting on both side, reloading models, I tried test exporting my model and to a skin which I set on my account, nothing works. We're on 1.12.2 version with the last version of the mod.
I'm kind of lost here. If someone could help me, it would be very appreciated.

Update:
Model won't load on server but when I take the original model it works. Also, it won't load under all conditions. I tried everything and I don't really want to redo it from the beginning. The update didn't do anything.

My model on my view :

Me on my friend view :

Original model :