**Disclaimer: I'm not an attorney, nor do I purport to be one. I am speaking on work experience without having explicit knowledge of your situation, the laws of your state or the technicalities of the situation at hand. Take all of the above into consideration when reading this response.**
The problem your mom is having is not that unusual. I work for a company that handles QDROs (among other things) and other pension administration issues.
What's probably happening is that the order your mom's attorney is drafting has to comply not only with current law (civil/common property, as well as IRS code) but also with the pension plan document (the legal document that the company signs to set up the rules of the pension plan.)
While I can't say what the exact problem is, it sounds like your mom's attorney might be trying to get something that isn't allowed- exceptions can be made for one reason or another but rarely are they granted outside of any explicit reasons stated in the pension plan document.
Sometimes these things take time to get worked out- your mom is entitled to her half of the pension benefits but if you are concerned that she is not getting her due share (i.e. the money is in the pension account, earning interest, and she's got nothing right now)- consider the following:
1. The payment she is due probably won't come in one big check- so if his pension is worth, say $200,000, she's not likely to open the mail box and have a check for $100,000 sitting in there. It's likely to come in monthly installments once your father is eligible for his pension. In other words, until and unless your dad retires or becomes eligible for his pension, she probably won't get anything until he does, and then it's likely to be a monthly pension check, the amount of which will be calculated by an actuary or someone else who does pension benefit administration (probably the same third party who is doing the QDRO).
2. The order is there- it's just a matter of getting the legalese hashed out. They are probably going over some of the more technical things- they aren't fighting over whether she's entitled to the money- she clearly is, according to the judge.
3. It's not uncommon for the process to take awhile. I am frankly surprised that the third party even talked to you- unless you have power of attorney or explicit permission from your mother, it could be considered violation of privacy. I've seen QDROs take upwards of 2-3 years to get settled- that's on the extreme side.
4. It's very likely that the amount in the account used to determine the pension amount will be balance that is in the account when the order is settled- not necessarily the date of the divorce. Remember, if they aren't divorced, they are still legally married, even if they are going through the process. Your mom might want to find out what the pension plan rules are regarding the date used to determine QDRO benefits (could be his retirement date, date of QDRO, date of divorce, etc.)
If your mom's attorney is being honest with you, let them keep working on it. If it takes longer or it seems like something is fishy, have your mom write a letter to the judge letting them know that the situation isn't resolving- and they may end up being able to expedite the process. Be persistent but not pushy, and remember that the pension income is supposed to be for your mom to live on when she's retired.
Be patient- but persistent- and good luck!