Hi there,
I listened to the recording a few times through. And, perhaps you have an up and coming paranormal investigator for a brother. But I'm going to share some advice through you for them.
While I heard a "yes", it was also difficult to cancel that out from the heavy breathing that came across as almost a light wheezing from his friends. At this point, I'd say it was more of the heavy breathing than anything else. But I'm not saying this to discourage them in any way. And what they need to understand is that, just because all the EVP's have voice on them with the different ghost hunting shows on television, does not mean that every time an EVP is done, that you will actually get a reply.
With that said, tell them please that they had some good questions but no whispering after a question has been asked. They might want to carry a watch or something with them that has a second hand on it so they can allow for 10 to 30 seconds after a question for "quiet time" from them so if a response is given, it could be better picked up.
Thanks for sharing!