A copy of the Complaint can be found
here.
I don't think Dominion was smart for filing this lawsuit. Giuliani almost certainly does not have significant assets, so Dominion is not going to recover what they are alleging are damages even if they win the case, and the case will give an opening for Guiliani to look for and air out any potential dirty laundry of Dominion's employees, and scrutinize Dominion itself. I doubt the outcome of the case will change many minds regarding Dominion, including those that are decision-makers deciding if local governments will employ Dominion.
It’s not even about being smart or not, it’s just a way of making a court say that he should shut-up for his claims being totally wrong and having no backing in the least.
I assume they also want the courts to show that everything he has said is wrong as a way to ensure that people on the state and local level will continue to buy their machines — as places where Republicans hold power are going to be wary about using these systems if their voters think they enable fraud.