I’ve gone through the game log, and the errors visible there have nothing to do with the crash. Most of the time, it’s just variables that can’t be found.
For example, M28 tries to access a variable where a number is expected, but nothing is returned. Here, the 92,574 error messages could have flooded the log and caused an issue with memory management. (I don’t think so, though — we’ve had worse log spam before, and the log continued to write.)
Brewlan expects a variable named TDFShipGaussCannonProjectile, which doesn’t exist. However, this only causes a standard projectile to be used and shouldn’t crash the game.
My gut feeling tells me that a mod like Buildable Lower Tiers Experimentals in Factories for Total Mayhem, Kennel Engineering Stations for All, or Reclaim Turret Aggressive is responsible. Most likely, it’s a modified unit where the engine expects certain values that aren’t present. But as I said, this is just my gut feeling, so it’s more guessing than knowing.
The only recommendation here is to thoroughly test the mods one by one. Even if you’re 100% certain which mod is causing the issue, debugging it is still difficult (to actually fix the mod).