Matter/Antimatter Asymmetry sans CPT Violation

So, what if matter/antimatter asymmetry in our universe can be explained without CPT violation? Basically, suppose the matter/antimatter in our universe is shaped like a 4-dimensional yin-yang. There’s an overabundance of matter (vs antimatter) at the big bang. However, the primordial antimatter could just a time-reversed chunk of matter from a mirror universe. This ‘chunk’ could be the only remnant after our universe collides perfectly with its antimatter mirror image:

So, rather than ending with a big crunch, or expanding forever, the universe would collide with its mirror twin, annihilate, and the remaining matter from our universe would continue on to the ‘gninnigeb’ of the mirror universe (ie the ‘gnab gib’). I guess this is sort of like the big crunch theory, except:

1. there’s a giant matter/antimatter annihilation event at the ‘end / dne’ of the universe
2. there is no CPT violation, and
3. it explains matter / antimatter asymmetry.

See also: https://arxiv.org/abs/1803.08930