Never been to Waverly Hills myself but it's on my list, been doing a fair bit of research on it for a potential trip over from Leeds next year. The EVP stuff people have captured there is genuinely hard to dismiss, some of those recordings from the body chute are proper unsettling.
What I will say is I'm skeptical of a lot of the "famous" haunted locations because the ghost tourism industry kind of ruins them, you get too many people tramping through contaminating any decent recordings. So I'm curious whether people who've actually done serious investigation there found it worthwhile or just a bit of a tourist circus.
Anyone done overnight sessions with proper kit rather than just the standard tour? Would love to know what floor you found most active if so. The 4th and 5th are always mentioned but I wonder if thats just because its what gets talked about online rather than actual evidence.