Absolutely there is the potential for problems. If one survives, or backs out, they could be criminally charged with a charge like aiding and abetting suicide, possibly even worse if it could be shown that they furnished materials to the other person who died. And then there is the potential for civil penalties if the family of the person who died decides to sue the other one who survived. Even if both parties die, there is still the potential for civil litigation against one party's estate, or even against both decedent's estates from the families of either decedent. If you have nothing, though, then there really is nothing to go after.