I an curios, why can't she contact a solictor in whatever country to make an application fro annulment in PI.
In Uk law if she advertises with the area she last knew her husband to be - for him to contact XXXX. NO reply she can legally assume he's dead onteh 7 year ruling.
It could also be that the ex, is married again ( it does happen I am told) or at least living with his latest family and not intersted in becoming involved with solicitors and courts.
I woul dsuggest a visit to an International layer/solicitor and ever the PI embassy for guidance.