This sounds like a bad situation.
-Don’t get “Brain raped” - if any of your knowledge is in conflict you need to hold it closely. They may just want to see what you’re working on then never speak to you again.
-I have had a friend with a NC who wanted to go to a competitor have a similar issue where legal action was brought up, and the hiring company backed down from offering him employment. This left him with no place to go which was not a good situation.