It was not a an issue about private persons or libel, but an issue of the selection process of the federation in general.
The public comments were made by the secretary of the club. In response, the judo federation suspended the entire club for 6 months with as justification "against the spirit of Judo and contrary to the ethos of the sport".
There are about 70 members in the club, who potentially are temporarily affected by the decision.
The decision does not seem to have been preceded by much due process, and seems to have been more an act of retaliation than protection again libel or a correction of facts.
The penalty was issued by the executive branch of the federation, which seems to operate without separation of powers (executive, legislative, judicial), hence joining the process of prosecutor, judge and jury in one and the same entity. The club was not heard prior to judgment and the federation violated its own rules.
The club has filed suit. The incident took place in Europe (Ireland). The case is widely reported in national newspapers, and not about private persons. It is, however, not possible to independently assess the correctness and completeness of the news reports: