I've found 2 burials on Deceased Online but one is West Yorkshire and the other Cheshire!
First of all, I would send off for the death certificates and then contact the local council services. If you need to details to send off for the Certs, let me know and I'll give you the ones I've found. The death Certs won't tell you where they are buried but it will give you some more info about what happened, which may in turn point you in the right direction.