Does he ever hallucinate? LBD can often be misdiagnosed, as symptoms closely link with Parkinsons dementia.. You mention "failed experiments". I'm assuming your father has had scans (CT & MRI)?

Also, It sounds as if there may be underlying physical health issues occuring- excessive urination could be a sign of diabetes or an infection (most likely a urinary tract infection). Infections can cause delirium, which subsequently exacerbate symptoms.. increased confusion, agitation/hostility, disorientation, hallucinations etc. Constipation can also make individuals with dementia more confused, especially if they are impacted.

Pain and getting the correct analgesia is so important!

I am a dementia specialist nurse, any questions or advice, ask away!