Continuity mistake: At the end when Audrey is drinking booze during take off, Jerry says "I love you" to her. Her drink instantly empties itself despite being full in the previous shot.
Continuity mistake: At Max's birthday party when Audrey is bending down next to Max, she tells him that his father is sorry for not being there, and tells him to make a wish. As the shots go from Max to his mom and back, Audrey's hair is behind her ear, then her bangs are loose, then behind her ear again, etc.
Continuity mistake: Outside the court at 2:15 when Fletcher is first talking to his son in his cell, the clock has the sun lighting up half its face. When he hangs up, the sun disappears from shining on the clock only to reappear again towards the end of the scene when he is gagging and walking away from his client.
Continuity mistake: When Fletcher spits water on himself while listening to the tape in court, the amount of water on the left lapel of his jacket changes from shot to shot from a little to a lot.
Continuity mistake: When Greta is asking Fletcher about her raise, the clock on the wall behind his desk says either 11:05 or 12:05 (hard to be sure). When he was on the phone with the judge, he said court started in a half hour, but when the courtroom scene starts we focus on the clock showing the time to be 1:30.
Continuity mistake: At the end when Fletcher is talking to his wife, there is a reflection of an outside window in the background showing a overcast but daylight sky in the window. However, when the camera pans away from the house we see that it's instantly night.
Continuity mistake: When Fletcher deposes the boyfriend on the stand, the water stain on the left lapel of his suit grows significantly when he stands up compared to when he was sitting.
Answer: First of all, she's not "on the hook" anyway...this is a divorce proceeding, not a criminal trial. And second, this film has multiple inaccuracies in its depiction of the legalities involved (see Legal Eagle's two-part analysis on YouTube for a very good rundown); the fact that no-one brings up fraud is the least of them. It's not important to the plot, so it is simply brushed aside, counting on us (the audience) not worrying too much about it, like so many other lapses of reality in comedy movies.