While the TA was not able to get the results I had hoped for, it was not due to lack of effort on their part. He did handle all the communication with LX and LH on my behalf and tried to point out their responsibility in this case. Unfortunately, he could not convince LH to own the responsibility. At my request, the TA also escalated it within the agency to write to LH management in an effort to resolve the issue.
So I have to say that the TA DID all that he could and it was not for his lack of effort that the case is not settled.