If you really have reached the end of the line with the usual routes, there is always the option of sending a PM to BAMissingAvios, which is actually a very small team (rather than one individual) who have helped a large number of FTers in the past. I hesitate to suggest them other than for complex situations such as yours where no-one appears willing or able to take responsibility for resolving it, but it may now be appropriate to take that route.