its a cryptocurrency, the courts legitimacy would likely come from the community forking as necessary to resolve issues as identified by the court, in the same way the us judicial branch gets its legitimacy from the us executive branch employing force as necessary to resolve issues as identified by that court.

its a broader group to convince, sure, but there is a clear 'or else' from which the court can get that legitimacy. 'return the money or else we will return it for you' is a meaningful or else