Michael Bay isn't involved in the suit, but D.W. Productions and Film Industry Location Management Services and the location managers on the job are. According to Deadline, back when the incident first occurred, Paramount claimed Cedillo wasn't directly involved in a stunt and that the accident was a freak occurrence. The studio said her car was over 500 feet from the action and that it was a flying metal object and not a towing cable that caused the injury. Paramount also claimed that the reshoot had nothing to do with the accident, rather a "timing issue."
Clearly Paramount's story and the local news report clash quite a bit, so it looks as though this could become a complicated issue. In the official suit it says that it was a stunt car that was being pulled by a cable from a flatbed truck. That stunt car was intentionally crashed while going over 50 mph. The document claims the studio was negligent in a number of ways including failing to secure the stunt car and failing to offer proper safety precautions to Cedillo. It goes on to say Cedillo will endure future suffering and "has become disfigured and disabled." Her demand is in excess of $50,000.
Perhaps this would be a matter for discussion if we were talking about an independent studio, but this is Paramount Pictures. This is a production rumored to have a $400 million budget. Yes, Bay refuted those claims, but odds are this film has a nice chunk of cash to work with. The studio can do much more than issue a statement saying, "We are all terribly sorry that this accident occurred. Our thoughts, prayers and best wishes are with Gabriela, her family and loved ones;" they can easily compensate her.
Of course there's always the concern that Cedillo could be exaggerating in an effort to make some easy money, but considering the turmoil that's gone on already with the film, the severity of the incident is quite plausible. The production lost one of its stars, Megan Fox, and there was the run-in with the National Park Service concerning Bay's plan to shoot in Washington, D.C., not to mention the widespread concern that 'Transformers 3' could be as awful as the second, 'Revenge of the Fallen.' However, all of those roadblocks are mere inconveniences compared to the pain Cedillo is reportedly enduring.