What legal recourse do we have if the vehicle that was awarded to ex is still in husband's name and ex is not taking steps to have it changed?

When my husband's divorce was finalized, his ex-wife was awarded two of the three vehicles. One vehicle was in my husband's name. The separation agreement states that "Simultaneously with the execution of this Agreement, each party agrees to execute and acknowledge all documents, including the certificate of title and Gift Certification Form, which may be necessary to transfer all of his or her rights, title, and interest in the other party’s vehicle (s) to the person entitled to retain such vehicle. Each party shall promptly apply for and obtain a new certificate of title and registration for the automobile in his or her own name. All costs of transfer, including titling fees and motor vehicle transfer taxes, if any, shall be paid by each party for the vehicle they are entitled to pursuant to this Agreement. "To date, this has not happened. The vehicle is still solely in my husband’s name. Given that they are no longer related, he cannot gift the vehicle to her now - she balked at the idea of needing to do a $1 bill of sale, having to pay taxes on it, and having to pay to have the car inspected. Most recently, she has stated she doesn't want the vehicle, and would like to sell it. This means getting the vehicle ready (it's currently not driveable), inspected, and having my husband do a limited power of attorney so she can sell it. However, she is not planning to do this for several more months. What type of recourse is available to my husband at this point? Also, am I correct that, should something happen to my husband, the vehicle would transfer to my name since it technically is still his property? This sounds messier than it needs to be at this point, and I would like to have some kind of resolution immediately, we just are not sure how to "force" the issue with his ex-wife. Thank you.