a theory of everything would have to have quantum mechanics as an emergent theory and quantum mechanics is fundamentally non-deterministic. and even if it was,

a theory of everything would have to have quantum mechanics as an emergent theory and quantum mechanics is fundamentally non-deterministic. and even if it was, a theory of everything is almost certainly not going to be practically computable for the same reason that even basic non-relativistic quantum mechanics cannot even solve for a reasonably sized molecule numerically (let alone exactly - just as classical mechanics is unsolvable for more than two bodies)