Mums lost wedding ring

My mum died in hospital just over a week ago. Somewhere between the care home and hospital my mums wedding ring and silver cross and chain have gone missing. I reported it to the Bereavement Team at the hospital and she said that nothing was documented about her having jewellery. The care home are ‘99.9%’ sure she was wearing both items when she left that day.
This is so upsetting for both myself and my sister, and no one seems to be taking any responsibility. I really don’t know what to do.
Has anyone else ever experienced anything like this?