did you reach out to people on LinkedIn? Like I say concierge (and some customer service agents) are great when its a task they can go and find the answer but as it needs to be passed from them to somebody else and you have to hope that somebody has the power they are not then as great. You need to go for the very top people and either hope you get lucky and its them or they can pass a message down (not up) the chain so it gets done as a priority, currently your issue will just be in an inbox with others on top of it.