Well they pretended like Snyder had no hand in WW so...
If that's the price to pay for DCEU to get some peace, I guess Snyder is the hero we needed but didn't deserve.
As for the reshoots, they're meant to make the movie better, after they received some reviews from their screenings, so they're putting their money into the project and try to improve its shortcomings.
I also don't think they have much action sequences planned for those reshoots, sounds more like character scenes and "flow" than set piece. So the CG should be fine, outside of this mustache disaster.
Hopefully this time around they had the right people giving them the good feedback. Because whoever was fine with BvS needs to be fired forever.