I just watched the latest episode again, and I think Wakefield's helper is Chloe.
In the church, you see Wakefield walking across the sanctuary just as the car pulls up, which draws everyone's attention to the door. Chloe's there, and that's when she disappears without a sound. Wouldn't she have gasped or screamed, even involuntarily?
Wakefield keeps her alive to trap the others, and Cal comes to her rescue. She leads Cal onto the bridge. She jumps off the bridge voluntarily, because Wakefield knows that Abby and Henry can see what's happening. I think her jumping was a ruse, and she's still alive.
Or she may not have wanted Cal to be killed, and jumped when Wakefield betrayed her.
I was a little frustrated with some of the plot holes this week. Trish should have shot Wakefield in the Cannery when she had the opportunity. Shane should have known that Wakefield had a three-foot-reach advantage with his gigantic knife on a stick. And Cal should not have been able to lift 100-pound Chloe out of that storm drain, having just had a bullet dug out of his shoulder and being full of amateur stitches. Cal should have been much, much weaker.
Wakefield being able to kick in the Cannery door, and take it right off the hinges puts him in the "unnatural strength" killer category. Thinking you can take him out with a shotgun, let alone a knife, is rather foolhardy.