Assuming the recruiting manager is non technical, he should have referred to the team in need when he received the "specification" email, something like "what should I do with this candidate?". A 5min chat with engineers would have clarified the situation and 5min to send an answer to the candidate. Same for the feedback request.

Seems like he did none of it, and in this company people do not talk and everyone is left guessing what is work consists in, which resonates strangely with the take home assignment directives. What an horrible workplace it would be.