The third party administrator is bound by its contract with the employer. If the employer does not sign or have the appropriate signature authority, the third party administrator is hamstrung. However, I suggest that you consult with your current employer's third party administrator to get guidance and assistance.
If your old employer does not cooperate, the employer may be violating federal law, particularly ERiSA (the Employee Retirement Income Security Act of 1974), and you may have to retain an attorney to write a demand letter to request compliance. The United States Department of Labor has web pages devoted to providing guidance, and answering questions like yours. The web address for the page detailing the situation where you file a claim for retirement benefits is:
The waiting period can be as long as 90 days. If you believe that you are being given the run around, or the company has failed to honor its obligations, you can contact the nearest office of the Department of Labor’s Employee Benefits Security Administration (EBSA) about your rights. The contact information for the Dallas Regional Office is:
Dallas Regional Office
525 South Griffin St, Rm 900
Dallas, TX 75202-5025
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