Continuity mistake: When the group enter the parents' room as superheroes, the father's right foot is covered up by the sheets. A shot later, it's not.
Continuity mistake: On the bridge, when Freddy grabs both cars and stops them from falling down, the driver on the left pops his head out the window, then back in, and then he pops it out again. A mere frame later his head is inside and his body is in a different position with both hands on the wheel.
Continuity mistake: When Shazam is at the shrink, the way his cape lies under his body, plus how far it is extended up to, changes between shots.
Revealing mistake: During the havoc at the museum, a visitor jumps headfirst into a stone column that falls apart. The volute falls to the ground and bounces around, revealing it's a prop.
Continuity mistake: When Billy and Freddie discuss about the one rule, Billy's head is either facing ahead or sideways between shots. No continuity at all.
Answer: The dinner scene, where Wonder Woman has the head of the Wizard, never happened. There's no indication they knew each other, let alone were friends. In the realm where superheroes actually do exist, there'd really be no reason why she, Superman, who is supposed to know them too, or any other hero wouldn't be there to help. So the only answer would be an unsatisfactory one that sounds pedantic: she didn't help because it's a Shazam movie and not a WW or JL movie. One could say that she and the other heroes were busy with fighting crime/battles in their own city or they didn't know they needed help. She only appears at the end, it seems, to restore the god realm. It's also been said they didn't think Gal Gadot would be available to shoot her cameo scene, so Wonder Woman may not have been in the film because of a scheduling conflict. But to me, if she was meant to be in the film, they would have secured her availability long before shooting.
Bishop73