First and foremost, so sorry for your loss.
The e-mail route is, I'm sure, the best way to handle this situation. Why you haven't received a reply on such a delicate subject in this many months is a bit concerning, but I am sure in order to satisfy this request, they will need some type of personal information verification. Without it, there would be lots of shady requests for credit transfers, etc. They do have some contacts listed that are available via the phone if you do a bit of digging. If the E-mails aren;t answered, I would proceed that way to light a fire under the right person.
Just to be safe, you should be using:
members@worldgolftour.com