A few points here:
-If they publicly disclosed that content, sharing that project via a screenshot, or any assets they provided on their website is not in breach of NDA. That content was made publicly available and your documentation of it should not be an issue, unless it was later retracted. Better yet, just include a URL.
-As people have mentioned, just because they have disclosed exhibits A,B,C would not give you permission to share more sketches, development work, or other projects publicly. Those are still protected by your original contract and many clients prohibit disclosure of development work especially if they reserve the rights to use it later. That would depend on the contract signed and if you do not have visibility to that service agreement you should not publicly share any of that content.
-Lastly, if the job interview is not in a competitive space, and you can share development work in person or under lock and key (password protected site or in person presentation that you don’t leave behind) you could decide to do that. Most designers have done or will do this at some point. With that said, I also know of someone who lost their job because they shared an early concept with someone who was friends with their old boss, and they immediately reached out and said “hey, saw that new widget you’re working on”. That however is a different situation from it ending up in the public space.
I would simply provide a URL to the website you mentioned and say “I worked on this and can discuss more in person but can’t share any additional assets at this time”. The last thing you would want is to find out it was an elaborate phishing scheme.