You need a lawyer.
I'm not a lawyer, so I won't even pretend to give legal advice. However...
You don't say what sort of trust this is, why it was established, or who has control of the trust.
If the judge actually did rule, then contact the court and get a copy of the judge's opinion. However, from what you've said, the judge approved the price; it's one of the beneficiaries of the trust who is refusing to give his/her assent. In that case, a lawyer might inform you that the individual (perhaps the trustee?) is acting counter to the judge's order.
So: You need a lawyer.