I know you’re frustrated, and angry, but from what you’ve provided, I think the problem is pretty obvious.
The combination of detereorated lasers and worn tanks is enough to push your prints into failure mode. It’s even more obviously the problem since things used to work. The variable is that you used the equipment, which does wear, and eventually wears out. Wear on lasers + tanks is super additive, meaning you have less and less leeway as both move toward EOL. And then, one fine day…
It’s a system, no different from the tires and brakes on your car; if one or the other is good, you might be ok in a fast stop. If both are worn, your air bag’s gonna explode one day.
So the newer machine gives good prints? What else changed?