The other party wants a change of venue and will not discuss mediation until after a hearing to change venue.
After the hearing is too late to do the mediation to change venue. You can always argue to the court that the other party refused to attempt mediation before going to court. The judge's response will depend on what your current order says about mediation before bringing a motion before the court. You should contact an attorney in your area to review the current order and offer you advice.
If the case is in court, ask the court to order mediation.
If they refuse to attend then, they risk contempt charges.
If the mediation really is "court ordered" then they need to comply with the court order. A Court enforces its orders through the contempt power, and the Court can fine them or possibly put them in jail for contempt if they don't participate in the mediation. But they are not required to settle with you. So they do have an incentive to comply with a court order to mediate, by showing up for the mediation.
This answer is intended as general information and not as specific legal advice.
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