Every jurisdiction is different, but in Mass the US District Court can take 2-6 months to render a decision, which can then be appealed as well. The USDCT can look at the decision, whether the Judge applied the law correctly, if you have many problems, whether they were all taken into account, and if the decision was properly made. One thing the appellate lever cannot review if the Judge's decision on your credibility and veracity. Claims at the USDCT are difficult and can take a long time, with many motions and steps to go through.
First ask your attorney. Second, if you cannot reach your attorney, contact the magistrate or judge's secretary. Since you lost at the ALJ level and the AC level you may want to also file a new claim while you are waiting for this decision.
This response is meant to be information only and should not be considered to be legal advice. This information is not meant and should not be construed to be the formation of an attorney client relationship. I practice Virginia Workers compensation law and Social Security Disability law.
As it relates to your question regarding a congressional inquiry, I recently had a client contact their US Senator's office regarding and inquiry while we were in USDC. The response from the Senator's office was that they were unable to make an inquiry due to the separation of powers. (Congressional vs. Judicial branches of government).
I too would recommend that you reach out to your attorney for a status on your case. USDC cases can take a year or more in my jurisdiction and there are long expanses of time where you are just waiting for an action to be taken by the Defendant or for a ruling from the Court.