Gustard says in post-match interview that it's a 'severe knee injury' for Earle so presumably our until next season (Murley was dislocated elbow.)
Interestingly he then says those two have played a lot because of their 'attitude and willingness to learn'. He then immediately namechecks Walker, Visser, R. Chisholm and Ibitoye (in that order) saying 'we've got options and if someone sticks their hand up and says "pick me" then they're going to get picked.'
Implies strongly that attitude is why Walker and Visser haven't been picked so far...