YIKES! This is pretty wild!! Do you have any idea how old the house might be, Grim? Just curious. It's too bad that the owners are afraid to let anything out about a "possible" (let's make that "probable"!) haunting going on here. With all of the deaths here over a period of time, that by itself is enough to leave something behind in the way of spirit activity... and, strangely enough, renovations and changes to a house tends to bring out even more paranormal activity, especially in a place with a history like this one! It would be very interesting to do some EVP's here. Are there people living in the house at present? If there aren't, maybe some EVP's could be captured from outdoors? Someplace near the house, if you would be allowed to do this without causing problems for yourself, or anyone else... thinking you are a burglar and calling police, or worse!! You don't need anyone unloading their gun in your direction.
This sounds sooo interesting, I really wish they would allow someone to come in and investigate this. There are just too many very strong signs of some rather intense paranormal activity going on, to just brush it aside and sweep it under the proverbial carpet.
Maybe the owner will have something happen that might change their mind...