Taking a step back. Generally speaking, the attorneys for both parties use the divorce decree to prepare a Domestic Relations Order (DRO). That Order is presented to the Plan Administrator (PA) for review (is it understandable, does it violate any plan provisions). The PA is not looking to see if the DRO satisfies the divorce decree, they are just looking to see if it complies with the plan's provisions and it understandable. It is up to the attorneys, participant, alternate payee to ensure the DRO satisfies the provisions of the decree. If the DRO satisfies all of the PA's requirements, they tell both parties that the DRO is "Qualified" making it a QDRO. QDRO is then sent to the court for approval. (I am just speaking in generalities, sometimes the court approval is requested before the PA's review, but that doesn't change the fact that the PA is the one who makes it a "Qualified" DRO.)
Does Ford GRP go ahead automatically and enforces QDRO for pension per the divorce decree, or do they have to have a QDRO paper filed? Ford is only obligated to enforce a QDRO. If no QDRO, then no action. If Ford knows that a DRO is forthcoming, or maybe forthcoming, they can hold a portion of your benefit until they either have a DRO to review, or a limited amount of time has passed. They should have "QDRO Procedures" that specify their rules, but generally, they notify both the participant and the AP that they have received a request for payment, they understand a DRO might be forthcoming, they will escrow an estimate of the APs benefits for some period of time (usually 180 days). If no DRO is received within that time period, they will release the escrowed payments to the participant.
Can she go ahead and file for a QDRO now after 20 years? yes
If the plan admin has a QDRO on file, shouldn't I, been noticed about it? Yes. You can always request to see a copy of it. If one exists, you, or your attorney, signed it.