Put aside Lyons' and De Las Heras' competence (or lack thereof - although, I don't think they're the two worst of the lot) for a minute, and if what Lyons accuses is true is that he was told "We wanted to go with younger refs" this does open a can of worms for age discrimination cases.
If you or I, as normal workers, were told that in our jobs, then we'd definitely win a case at the tribunal for unfair dismissal.
But can someone be terminated from a job in which they physically need to be able to perform at a high level, and be given the excuse we're going with younger refs? I would say only if the NRL can prove that physically Lyons and De Las Heras aren't fit to do their jobs. I would say that would be hard to prove unless they had some sort of medical evidence. If they used the excuse "we don't think you're performing at the level required anymore" it would've been a lot easier to get rid of them than "we want to go with younger refs", they've sort of opened a minefield there.