

I definitely had to look it up, as it’s difficult and a bit confusing to parse and makes use of some rather dated slang, but yes it does make sense.
It means that buffalo from the city called Buffalo, who bully other buffalo from Buffalo are in turn bullied by buffalo from Buffalo.
Depending on your setting and desired outcome for the poisoner, uraninite (aka pitchblende) might be an option. It has historical uses in glass making and pottery glazing, which could provide justification for why someone would have it.
It contains Uranium, which is radioactive, but I don’t believe will bioaccumulate, but can build up on surfaces, tools, and clothing providing a source of long-term radiation exposure. In addition, it contains lead, which does bioaccumulate, providing a source of gradual long term poisoning as well as radium which also bioaccumulates and is radioactive, providing an additional source of longterm radiation exposure.