How to get a reference to "context" in onBeforeSubmit

I have an SPFX project that is a form extension using the React framework. I am debugging the edit form. I do some validation in the onBeforeSubmit method and I do not seem to be able to get a reference to the context using this.context. 

I pass the context into the <DynamicForm element using props. The form loads the listitem correctly and saves changes correctly, but I still can't reference these items within onBeforeSubmit. 

I think I'm just missing something within SP or React and thought I'd post here to see if someone had an idea as to what it may be.

Thanks