Dispute mediation usually requires the agreement of the two parties to the authority of the mediator.
If what is in dispute is a lease, contract or other legal circumstance, mediation may have to have legal approval such as with a judge.
Most people prefer to avoid disputes in general and particularly those in which they are not involved. It might be possible to enlist the aid of someone from a church to act to help settle a dispute, but even here the odds would be against you.