[noone_important]

Just because they are not mainstream, you definitely can have lorentz violation in string theory [0]. Spontaneous symmetry breaking can lead to induced finsler geometries, which can basically have multiple light cones (when there was the "faster than light neutrinos" result on the table. Some people used finsler spacetime to explain them).

So you made your prediction only by choosing an axiom.

There is a reason that even some proponents of string theory call it the theory of anything.

[0] https://arxiv.org/abs/0708.2250